1. Overview

Keycloak supports both OpenID Connect (an extension to OAuth 2.0) and SAML 2.0. When securing clients and services the first thing you need to
decide is which of the two you are going to use. If you want you can also choose to secure some with OpenID Connect and others with SAML.

To secure clients and services you are also going to need an adapter or library for the protocol you’ve selected. Keycloak comes with its own
adapters for selected platforms, but it is also possible to use generic OpenID Connect Resource Provider and SAML Service Provider libraries.

1.1. What are Client Adapters?

Keycloak client adapters are libraries that makes it very easy to secure applications and services with Keycloak. We call them
adapters rather than libraries as they provide a tight integration to the underlying platform and framework. This makes our adapters easy to use and they
require less boilerplate code than what is typically required by a library.

1.2.4. Android

1.2.5. iOS

Apache HTTP Server

1.2.6. SAML

Java

Apache HTTP Server

1.3. Supported Protocols

1.3.1. OpenID Connect

Open ID Connect (OIDC) is an authentication protocol that is an extension of OAuth 2.0.
While OAuth 2.0 is only a framework for building authorization protocols and is mainly incomplete, OIDC is a full-fledged authentication and authorization
protocol. OIDC also makes heavy use of the Json Web Token (JWT) set of standards. These standards define an
identity token JSON format and ways to digitally sign and encrypt that data in a compact and web-friendly way.

There is really two types of use cases when using OIDC. The first is an application that asks the Keycloak server to authenticate
a user for them. After a successful login, the application will receive an identity token and an access token. The identity token
contains information about the user such as username, email, and other profile information. The access token is digitally signed by
the realm and contains access information (like user role mappings) that the application can use to determine what resources the user
is allowed to access on the application.

The second type of use cases is that of a client that wants to gain access to remote services. In this case, the client asks Keycloak
to obtain an access token it can use to invoke on other remote services on behalf of the user. Keycloak authenticates the user
then asks the user for consent to grant access to the client requesting it. The client then receives the access token. This access token
is digitally signed by the realm. The client can make REST invocations on remote services using this access token. The REST service
extracts the access token, verifies the signature of the token, then decides based on access information within the token whether or not to process
the request.

1.3.2. SAML 2.0

SAML 2.0 is a similar specification to OIDC but a lot older and more mature. It has its roots in SOAP and the plethora
of WS-* specifications so it tends to be a bit more verbose than OIDC. SAML 2.0 is primarily an authentication protocol
that works by exchanging XML documents between the authentication server and the application. XML signatures and encryption are used to verify requests and responses.

In Keycloak SAML serves two types of use cases: browser applications and REST invocations.

There is really two types of use cases when using SAML. The first is an application that asks the Keycloak server to authenticate
a user for them. After a successful login, the application will receive an XML document that contains
something called a SAML assertion that specifies various attributes about the user. This XML document is digitally signed by
the realm and contains access information (like user role mappings) that the application can use to determine what resources the user
is allowed to access on the application.

The second type of use cases is that of a client that wants to gain access to remote services. In this case, the client asks Keycloak
to obtain a SAML assertion it can use to invoke on other remote services on behalf of the user.

1.3.3. OpenID Connect vs. SAML

Choosing between OpenID Connect and SAML is not just a matter of using a newer protocol (OIDC) instead of the older more mature protocol (SAML).

In most cases Keycloak recommends using OIDC.

SAML tends to be a bit more verbose than OIDC.

Beyond verbosity of exchanged data, if you compare the specifications you’ll find that OIDC was designed to work with the web while SAML was retrofitted to work on top of the web. For example, OIDC is also more suited for HTML5/JavaScript applications because it is
easier to implement on the client side than SAML. As tokens are in the JSON format,
they are easier to consume by JavaScript. You will also find several nice features that
make implementing security in your web applications easier. For example, check out the iframe trick that the specification uses to easily determine if a user is still logged in or not.

SAML has its uses though. As you see the OIDC specifications evolve you see they implement more and more features that SAML has had for years. What we often see is that people pick SAML over OIDC because of the perception that it is more mature and also because they already have existing applications that are secured with it.

2. OpenID Connect

This section describes how you can secure applications and services with OpenID Connect using either Keycloak adapters or generic OpenID Connect
Resource Provider libraries.

2.1. Java Adapters

Keycloak comes with a range of different adapters for Java application. Selecting the correct adapter depends on the target platform.

All Java adapters share a set of common configuration options described in the Java Adapters Config chapter.

2.1.1. Java Adapter Config

Each Java adapter supported by Keycloak can be configured by a simple JSON file.
This is what one might look like:

You can use ${…​} enclosure for system property replacement. For example ${jboss.server.config.dir} would be replaced by /path/to/Keycloak.
Replacement of environment variables is also supported via the env prefix, e.g. ${env.MY_ENVIRONMENT_VARIABLE}.

The initial config file can be obtained from the the admin console. This can be done by opening the admin console, select Clients from the menu and clicking
on the corresponding client. Once the page for the client is opened click on the Installation tab and select Keycloak OIDC JSON.

Here is a description of each configuration option:

realm

Name of the realm.
This is REQUIRED.

resource

The client-id of the application. Each application has a client-id that is used to identify the application.
This is REQUIRED.

realm-public-key

PEM format of the realm public key. You can obtain this from the administration console.
This is OPTIONAL and it’s not recommended to set it. If not set, the adapter will download this from Keycloak and
it will always re-download it when needed (eg. Keycloak rotate it’s keys). However if realm-public-key is set, then adapter
will never download new keys from Keycloak, so when Keycloak rotate it’s keys, adapter will break.

auth-server-url

The base URL of the Keycloak server. All other Keycloak pages and REST service endpoints are derived from this. It is usually of the form https://host:port/auth.
This is REQUIRED.

ssl-required

Ensures that all communication to and from the Keycloak server is over HTTPS.
In production this should be set to all.
This is OPTIONAL.
The default value is external meaning that HTTPS is required by default for external requests.
Valid values are 'all', 'external' and 'none'.

confidential-port

The confidential port used by the Keycloak server for secure connections over SSL/TLS.
This is OPTIONAL.
The default value is 8443.

use-resource-role-mappings

If set to true, the adapter will look inside the token for application level role mappings for the user. If false, it will look at the realm level for user role mappings.
This is OPTIONAL.
The default value is false.

public-client

If set to true, the adapter will not send credentials for the client to Keycloak.
This is OPTIONAL.
The default value is false.

enable-cors

This enables CORS support. It will handle CORS preflight requests. It will also look into the access token to determine valid origins.
This is OPTIONAL.
The default value is false.

cors-max-age

If CORS is enabled, this sets the value of the Access-Control-Max-Age header.
This is OPTIONAL.
If not set, this header is not returned in CORS responses.

cors-allowed-methods

If CORS is enabled, this sets the value of the Access-Control-Allow-Methods header.
This should be a comma-separated string.
This is OPTIONAL.
If not set, this header is not returned in CORS responses.

cors-allowed-headers

If CORS is enabled, this sets the value of the Access-Control-Allow-Headers header.
This should be a comma-separated string.
This is OPTIONAL.
If not set, this header is not returned in CORS responses.

cors-exposed-headers

If CORS is enabled, this sets the value of the Access-Control-Expose-Headers header.
This should be a comma-separated string.
This is OPTIONAL.
If not set, this header is not returned in CORS responses.

bearer-only

This should be set to true for services. If enabled the adapter will not attempt to authenticate users, but only verify bearer tokens.
This is OPTIONAL.
The default value is false.

autodetect-bearer-only

This should be set to true if your application serves both a web application and web services (e.g. SOAP or REST).
It allows you to redirect unauthenticated users of the web application to the Keycloak login page,
but send an HTTP 401 status code to unauthenticated SOAP or REST clients instead as they would not understand a redirect to the login page.
Keycloak auto-detects SOAP or REST clients based on typical headers like X-Requested-With, SOAPAction or Accept.
The default value is false.

enable-basic-auth

This tells the adapter to also support basic authentication. If this option is enabled, then secret must also be provided.
This is OPTIONAL.
The default value is false.

expose-token

If true, an authenticated browser client (via a Javascript HTTP invocation) can obtain the signed access token via the URL root/k_query_bearer_token.
This is OPTIONAL.
The default value is false.

credentials

Specify the credentials of the application. This is an object notation where the key is the credential type and the value is the value of the credential type.
Currently password and jwt is supported. This is REQUIRED only for clients with 'Confidential' access type.

connection-pool-size

Adapters will make separate HTTP invocations to the Keycloak server to turn an access code into an access token.
This config option defines how many connections to the Keycloak server should be pooled.
This is OPTIONAL.
The default value is 20.

disable-trust-manager

If the Keycloak server requires HTTPS and this config option is set to true you do not have to specify a truststore.
This setting should only be used during development and never in production as it will disable verification of SSL certificates.
This is OPTIONAL.
The default value is false.

allow-any-hostname

If the Keycloak server requires HTTPS and this config option is set to true the Keycloak server’s certificate is validated via the truststore,
but host name validation is not done.
This setting should only be used during development and never in production as it will disable verification of SSL certificates.
This seting may be useful in test environments This is OPTIONAL.
The default value is false.

proxy-url

The URL for the HTTP proxy if one is used.

truststore

The value is the file path to a keystore file.
If you prefix the path with classpath:, then the truststore will be obtained from the deployment’s classpath instead.
Used for outgoing HTTPS communications to the Keycloak server.
Client making HTTPS requests need a way to verify the host of the server they are talking to.
This is what the trustore does.
The keystore contains one or more trusted host certificates or certificate authorities.
You can create this truststore by extracting the public certificate of the Keycloak server’s SSL keystore.
This is REQUIRED unless ssl-required is none or disable-trust-manager is true.

truststore-password

Password for the truststore keystore.
This is REQUIRED if truststore is set and the truststore requires a password.

client-keystore

This is the file path to a keystore file.
This keystore contains client certificate for two-way SSL when the adapter makes HTTPS requests to the Keycloak server.
This is OPTIONAL.

client-keystore-password

Password for the client keystore.
This is REQUIRED if client-keystore is set.

client-key-password

Password for the client’s key.
This is REQUIRED if client-keystore is set.

always-refresh-token

If true, the adapter will refresh token in every request.

register-node-at-startup

If true, then adapter will send registration request to Keycloak.
It’s false by default and useful only when application is clustered.
See Application Clustering for details

register-node-period

Period for re-registration adapter to Keycloak.
Useful when application is clustered.
See Application Clustering for details

token-store

Possible values are session and cookie.
Default is session, which means that adapter stores account info in HTTP Session.
Alternative cookie means storage of info in cookie.
See Application Clustering for details

The session id is changed by default on a successful login on some platforms to plug a security attack vector. Change this to true if you want to turn this off This is OPTIONAL.
The default value is false.

token-minimum-time-to-live

Amount of time, in seconds, to preemptively refresh an active access token with the Keycloak server before it expires.
This is especially useful when the access token is sent to another REST client where it could expire before being evaluated.
This value should never exceed the realm’s access token lifespan.
This is OPTIONAL. The default value is 0 seconds, so adapter will refresh access token just if it’s expired.

min-time-between-jwks-requests

Amount of time, in seconds, specifying minimum interval between two requests to Keycloak to retrieve new public keys.
It is 10 seconds by default.
Adapter will always try to download new public key when it recognize token with unknown kid . However it won’t try it more
than once per 10 seconds (by default). This is to avoid DoS when attacker sends lots of tokens with bad kid forcing adapter
to send lots of requests to Keycloak.

public-key-cache-ttl

Amount of time, in seconds, specifying maximum interval between two requests to Keycloak to retrieve new public keys.
It is 86400 seconds (1 day) by default.
Adapter will always try to download new public key when it recognize token with unknown kid . If it recognize token with known kid, it will
just use the public key downloaded previously. However at least once per this configured interval (1 day by default) will be new
public key always downloaded even if the kid of token is already known.

ignore-oauth-query-parameter

Defaults to false, if set to true will turn off processing of the access_token
query parameter for bearer token processing. Users will not be able to authenticate
if they only pass in an access_token

redirect-rewrite-rules

If needed, specify the Redirect URI rewrite rule. This is an object notation where the key is the regular expression to which the Redirect URI is to be matched and the value is the replacement String.
$ character can be used for backreferences in the replacement String.

2.1.2. JBoss EAP/Wildfly Adapter

To be able to secure WAR apps deployed on JBoss EAP, WildFly or JBoss AS, you must install and configure the
Keycloak adapter subsystem. You then have two options to secure your WARs.

You can provide an adapter config file in your WAR and change the auth-method to KEYCLOAK within web.xml.

Alternatively, you don’t have to modify your WAR at all and you can secure it via the Keycloak adapter subsystem configuration in standalone.xml.
Both methods are described in this section.

Installing the adapter

Adapters are available as a separate archive depending on what server version you are using.

Securing WARs via Adapter Subsystem

You do not have to modify your WAR to secure it with Keycloak. Instead you can externally secure it via the Keycloak Adapter Subsystem.
While you don’t have to specify KEYCLOAK as an auth-method, you still have to define the security-constraints in web.xml.
You do not, however, have to create a WEB-INF/keycloak.json file.
This metadata is instead defined within server configuration (i.e. standalone.xml) in the Keycloak subsystem definition.

The secure-deploymentname attribute identifies the WAR you want to secure.
Its value is the module-name defined in web.xml with .war appended. The rest of the configuration corresponds pretty much one to one with the keycloak.json configuration options defined in Java adapter configuration.

The exception is the credential element.

To make it easier for you, you can go to the Keycloak Administration Console and go to the Client/Installation tab of the application this WAR is aligned with.
It provides an example XML file you can cut and paste.

If you have multiple deployments secured by the same realm you can share the realm configuration in a separate element. For example:

2.1.3. JBoss Fuse Adapter

It leverages Jetty 9 adapter as JBoss Fuse 6.3.0 Rollup 5 is bundled with Jetty 9.2 server
under the covers and Jetty is used for running various kinds of web applications.

The only supported version of Fuse is JBoss Fuse 6.3.0 Rollup 5. If you use earlier versions of Fuse, it is possible that some functions will not work correctly. In particular, the Hawtio integration will not work with earlier versions of Fuse.

Securing Your Web Applications Inside Fuse

You must first install the Keycloak Karaf feature. Next you will need to perform the steps according to the type of application you want to secure.
All referenced web applications require injecting the Keycloak Jetty authenticator into the underlying Jetty server. The steps to achieve this depend on the application type. The details are described below.

The best place to start is look at Fuse demo bundled as part of Keycloak examples in directory fuse . Most of the steps should be understandable from testing and
understanding the demo.

Installing the Keycloak Feature

You must first install the keycloak feature in the JBoss Fuse environment. The keycloak feature includes the Fuse adapter and all third-party dependencies. You can install it either from the Maven repository or from an archive.

Installing from the Maven Repository

As a prerequisite, you must be online and have access to the Maven repository.

For community it’s sufficient to be online as all the artifacts and 3rd party dependencies should be available in the maven central repository.

To install the keycloak feature using the Maven repository, complete the following steps:

Within the /WEB-INF/ directory of your WAR, create a new file, keycloak.json. The format of this configuration file is described in the Java Adapters Config section. It is also possible to make this file available externally as described in Configuring the External Adapter.

Ensure your WAR application imports org.keycloak.adapters.jetty and maybe some more packages in the META-INF/MANIFEST.MF file, under the Import-Package header. Using maven-bundle-plugin in your project properly generates OSGI headers in manifest.
Note that "*" resolution for the package does not import the org.keycloak.adapters.jetty package, since it is not used by the application or the Blueprint or Spring descriptor, but is rather used in the jetty-web.xml file.

Configuring the External Adapter

If you do not want the keycloak.json adapter configuration file to be bundled inside your WAR application, but instead made available externally and loaded based on naming conventions, use this configuration method.

To enable the functionality, add this section to your /WEB_INF/web.xml file:

That component uses keycloak.config or karaf.etc java properties to search for a base folder to locate the configuration.
Then inside one of those folders it searches for a file called <your_web_context>-keycloak.json.

So, for example, if your web application has context my-portal, then your adapter configuration is loaded from the $FUSE_HOME/etc/my-portal-keycloak.json file.

Securing a Servlet Deployed as an OSGI Service

You can use this method if you have a servlet class inside your OSGI bundled project that is not deployed as a classic WAR application. Fuse uses Pax Web Whiteboard Extender to deploy such servlets as web applications.

To secure your servlet with Keycloak, complete the following steps:

Keycloak provides PaxWebIntegrationService, which allows injecting jetty-web.xml and configuring security constraints for your application. You need to declare such services in the OSGI-INF/blueprint/blueprint.xml file inside your application. Note that your servlet needs to depend on it.
An example configuration:

<?xml version="1.0" encoding="UTF-8"?><blueprintxmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.osgi.org/xmlns/blueprint/v1.0.0http://www.osgi.org/xmlns/blueprint/v1.0.0/blueprint.xsd"><!-- Using jetty bean just for the compatibility with other fuse services --><beanid="servletConstraintMapping"class="org.eclipse.jetty.security.ConstraintMapping"><propertyname="constraint"><beanclass="org.eclipse.jetty.util.security.Constraint"><propertyname="name"value="cst1"/><propertyname="roles"><list><value>user</value></list></property><propertyname="authenticate"value="true"/><propertyname="dataConstraint"value="0"/></bean></property><propertyname="pathSpec"value="/product-portal/*"/></bean><beanid="keycloakPaxWebIntegration"class="org.keycloak.adapters.osgi.PaxWebIntegrationService"init-method="start"destroy-method="stop"><propertyname="jettyWebXmlLocation"value="/WEB-INF/jetty-web.xml"/><propertyname="bundleContext"ref="blueprintBundleContext"/><propertyname="constraintMappings"><list><refcomponent-id="servletConstraintMapping"/></list></property></bean><beanid="productServlet"class="org.keycloak.example.ProductPortalServlet"depends-on="keycloakPaxWebIntegration"></bean><serviceref="productServlet"interface="javax.servlet.Servlet"><service-properties><entrykey="alias"value="/product-portal"/><entrykey="servlet-name"value="ProductServlet"/><entrykey="keycloak.config.file"value="/keycloak.json"/></service-properties></service></blueprint>

You might need to have the WEB-INF directory inside your project (even if your project is not a web application) and create the /WEB-INF/jetty-web.xml and /WEB-INF/keycloak.json files as in the Classic WAR application section.
Note you don’t need the web.xml file as the security-constraints are declared in the blueprint configuration file.

The Import-Package in META-INF/MANIFEST.MF must contain at least these imports:

Securing an Apache Camel Application

You can secure Apache Camel endpoints implemented with the camel-jetty component by adding securityHandler with KeycloakJettyAuthenticator and the proper security constraints injected. You can add the OSGI-INF/blueprint/blueprint.xml file to your Camel application with a similar configuration as below. The roles, security constraint mappings, and Keycloak adapter configuration might differ slightly depending on your environment and needs.

Securing an Apache CXF Endpoint on a Separate Jetty Engine

To run your CXF endpoints secured by Keycloak on separate Jetty engines, complete the following steps:

Add META-INF/spring/beans.xml to your application, and in it, declare httpj:engine-factory with Jetty SecurityHandler with injected KeycloakJettyAuthenticator. The configuration for a CFX JAX-WS application might resemble this one:

Securing an Apache CXF Endpoint on the Default Jetty Engine

Some services automatically come with deployed servlets on startup. One such service is the CXF servlet running in the http://localhost:8181/cxf context. Securing such endpoints can be complicated. One approach, which Keycloak is currently using, is ServletReregistrationService, which undeploys a built-in servlet at startup, enabling you to redeploy it on a context secured by Keycloak.

The configuration file OSGI-INF/blueprint/blueprint.xml inside your application might resemble the one below. Note that it adds the JAX-RS customerservice endpoint, which is endpoint-specific to your application, but more importantly, secures the entire /cxf context.

As a result, all other CXF services running on the default CXF HTTP destination are also secured. Similarly, when the application is undeployed, the entire /cxf context becomes unsecured as well. For this reason, using your own Jetty engine for your applications as described in Secure CXF Application on separate Jetty Engine then gives you more
control over security for each individual application.

The WEB-INF directory might need to be inside your project (even if your project is not a web application). You might also need to edit the /WEB-INF/jetty-web.xml and /WEB-INF/keycloak.json files in a similar way as in Classic WAR application.
Note that you do not need the web.xml file as the security constraints are declared in the blueprint configuration file.

The Import-Package in META-INF/MANIFEST.MF must contain these imports:

Securing Fuse Administration Services

Using SSH Authentication to Fuse Terminal

Keycloak mainly addresses use cases for authentication of web applications; however, if your other web services and applications are protected
with Keycloak, protecting non-web administration services such as SSH with Keycloak credentials is a best pracrice. You can do this using the JAAS login module, which allows remote connection to Keycloak and verifies credentials based on
Resource Owner Password Credentials.

To enable SSH authentication, complete the following steps:

In Keycloak create a client (for example, ssh-jmx-admin-client), which will be used for SSH authentication.
This client needs to have Direct Access Grants Enabled selected to On.

In the $FUSE_HOME/etc/org.apache.karaf.shell.cfg file, update or specify this property:

sshRealm=keycloak

Add the $FUSE_HOME/etc/keycloak-direct-access.json file with content similar to the following (based on your environment and Keycloak client settings):

This file specifies the client application configuration, which is used by JAAS DirectAccessGrantsLoginModule from the keycloak JAAS realm for SSH authentication.

Start Fuse and install the keycloak JAAS realm. The easiest way is to install the keycloak-jaas feature, which has the JAAS realm predefined. You can override the feature’s predefined realm by using your own keycloak JAAS realm with higher ranking. For details see the https:access.redhat.com/documentation/en-us/red_hat_jboss_fuse/6.3/html-single/security_guide/#ESBSecureContainer[JBoss Fuse documentation].

Log in using SSH as admin user by typing the following in the terminal:

ssh -o PubkeyAuthentication=no -p 8101 admin@localhost

Log in with password password.

On some later operating systems, you might also need to use the SSH command’s -o option -o HostKeyAlgorithms=+ssh-dss because later SSH clients do not allow use of the ssh-dss algorithm, by default. However, by default, it is currently used in JBoss Fuse 6.3.0 Rollup 5.

Note that the user needs to have realm role admin to perform all operations or another role to perform a subset of operations (for example, the viewer role that restricts the user to run only read-only Karaf commands). The available roles are configured in $FUSE_HOME/etc/org.apache.karaf.shell.cfg or $FUSE_HOME/etc/system.properties.

Using JMX Authentication

JMX authentication might be necessary if you want to use jconsole or another external tool to remotely connect to JMX through RMI. Otherwise it might be better to use hawt.io/jolokia, since the jolokia agent is installed in hawt.io by default. For more details see Hawtio Admin Console.

To use JMX authentication, complete the following steps:

In the $FUSE_HOME/etc/org.apache.karaf.management.cfg file, change the jmxRealm property to:

jmxRealm=keycloak

Install the keycloak-jaas feature and configure the $FUSE_HOME/etc/keycloak-direct-access.json file as described in the SSH section above.

Create a client in the Keycloak administration console in your realm. For example, in the Keycloak demo realm, create a client hawtio-client, specify public as the Access Type, and specify a redirect URI pointing to Hawtio: http://localhost:8181/hawtio/*. You must also have a corresponding Web Origin configured (in this case, http://localhost:8181).

Create the keycloak-hawtio-client.json file in the $FUSE_HOME/etc directory using content similar to that shown in the example below. Change the realm, resource, and auth-server-url properties according to your Keycloak environment. The resource property must point to the client created in the previous step. This file is used by the client (Hawtio Javascript application) side.

Create the keycloak-hawtio.json file in the $FUSE_HOME/etc dicrectory using content similar to that shown in the example below. Change the realm and auth-server-url properties according to your Keycloak environment. This file is used by the adapters on the server (JAAS Login module) side.

2.1.4. Spring Boot Adapter

To be able to secure Spring Boot apps you must add the Keycloak Spring Boot adapter JAR to your app.
You then have to provide some extra configuration via normal Spring Boot configuration (application.properties). Let’s go over these steps.

Adapter Installation

The Keycloak Spring Boot adapter takes advantage of Spring Boot’s autoconfiguration so all you need to do is add the Keycloak Spring Boot starter to your project.
They Keycloak Spring Boot Starter is also directly available from the Spring Start Page.
To add it manually and if you are using Maven, add the following to your dependencies :

To configure a Policy Enforcer, unlike keycloak.json, policy-enforcer-config must be used instead of just policy-enforcer.

You also need to specify the Java EE security config that would normally go in the web.xml.
The Spring Boot Adapter will set the login-method to KEYCLOAK and configure the security-constraints at startup time.
Here’s an example configuration:

If you plan to deploy your Spring Application as a WAR then you should not use the Spring Boot Adapter and use the dedicated adapter for the application server or servlet container you are using. Your Spring Boot should also contain a web.xml file.

2.1.5. Tomcat 6, 7 and 8 Adapters

To be able to secure WAR apps deployed on Tomcat 6, 7 and 8 you must install the Keycloak Tomcat 6, 7 or 8 adapter into your Tomcat installation.
You then have to provide some extra configuration in each WAR you deploy to Tomcat.
Let’s go over these steps.

Adapter Installation

Adapters are no longer included with the appliance or war distribution.
Each adapter is a separate download on the Keycloak download site.
They are also available as a maven artifact.

You must unzip the adapter distro into Tomcat’s lib/ directory.
Including adapter’s jars within your WEB-INF/lib directory will not work! The Keycloak adapter is implemented as a Valve and valve code must reside in Tomcat’s main lib/ directory.

2.1.6. Jetty 9.x Adapters

Keycloak has a separate adapter for Jetty 9.1.x, Jetty 9.2.x and Jetty 9.3.x that you will have to install into your Jetty installation.
You then have to provide some extra configuration in each WAR you deploy to Jetty.
Let’s go over these steps.

Adapter Installation

Adapters are no longer included with the appliance or war distribution. Each adapter is a separate download on the Keycloak download site.
They are also available as a maven artifact.

You must unzip the Jetty 9.x distro into Jetty 9.x’s base directory.
Including adapter’s jars within your WEB-INF/lib directory will not work!
In the example below, the Jetty base is named your-base:

$ cd your-base
$ unzip keycloak-jetty93-adapter-dist-2.5.0.Final.zip

Next, you will have to enable the keycloak module for your Jetty base:

$ java -jar $JETTY_HOME/start.jar --add-to-startd=keycloak

Required Per WAR Configuration

This section describes how to secure a WAR directly by adding config and editing files within your WAR package.

The first thing you must do is create a WEB-INF/jetty-web.xml file in your WAR package.
This is a Jetty specific config file and you must define a Keycloak specific authenticator within it.

The Jetty 9.1.x adapter will not be able to find the keycloak.json file.
You will have to define all adapter settings within the jetty-web.xml file as described below.

Instead of using keycloak.json, you can define everything within the jetty-web.xml.
You’ll just have to figure out how the json settings match to the org.keycloak.representations.adapters.config.AdapterConfig class.

You do not have to crack open your WAR to secure it with keycloak.
Instead create the jetty-web.xml file in your webapps directory with the name of yourwar.xml.
Jetty should pick it up.
In this mode, you’ll have to declare keycloak.json configuration directly within the xml file.

Finally you must specify both a login-config and use standard servlet security to specify role-base constraints on your URLs.
Here’s an example:

2.1.7. Jetty 8.1.x Adapter

Keycloak has a separate adapter for Jetty 8.1.x that you will have to install into your Jetty installation.
You then have to provide some extra configuration in each WAR you deploy to Jetty.
Let’s go over these steps.

Adapter Installation

Adapters are no longer included with the appliance or war distribution. Each adapter is a separate download on the Keycloak download site.
They are also available as a maven artifact.

You must unzip the Jetty 8.1.x distro into Jetty 8.1.x’s root directory.
Including adapter’s jars within your WEB-INF/lib directory will not work!

$ cd $JETTY_HOME
$ unzip keycloak-jetty81-adapter-dist.zip

Next, you will have to enable the keycloak option.
Edit start.ini and add keycloak to the options

#===========================================================
# Start classpath OPTIONS.
# These control what classes are on the classpath
# for a full listing do
# java -jar start.jar --list-options
#-----------------------------------------------------------
OPTIONS=Server,jsp,jmx,resources,websocket,ext,plus,annotations,keycloak

Required Per WAR Configuration

Enabling Keycloak for your WARs is the same as the Jetty 9.x adapter.
Our 8.1.x adapter supports both keycloak.json and the jboss-web.xml advanced configuration.
See Required Per WAR Configuration

2.1.8. Spring Security Adapter

To secure an application with Spring Security and Keycloak, add this adapter as a dependency to your project.
You then have to provide some extra beans in your Spring Security configuration file and add the Keycloak security filter to your pipeline.

Unlike the other Keycloak Adapters, you should not configure your security in web.xml.
However, keycloak.json is still required.

Spring Security Configuration

Java Configuration

Keycloak provides a KeycloakWebSecurityConfigurerAdapter as a convenient base class for creating a WebSecurityConfigurer instance.
The implementation allows customization by overriding methods.
While its use is not required, it greatly simplifies your security context configuration.

You must provide a session authentication strategy bean which should be of type RegisterSessionAuthenticationStrategy for public or confidential applications and NullAuthenticatedSessionStrategy for bearer-only applications.

Spring Security’s SessionFixationProtectionStrategy is currently not supported because it changes the session identifier after login via Keycloak.
If the session identifier changes, universal log out will not work because Keycloak is unaware of the new session identifier.

The @KeycloakConfiguration annotation is a metadata annotion that defines all annotations that are needed to integrate
Keycloak in Spring Security. If you have a complexe Spring Security setup you can simply have a look ath the annotations of
the @KeycloakConfiguration annotation and create your own custom meta annotation or just use specific Spring annotations
for the Keycloak adapter.

XML Configuration

While Spring Security’s XML namespace simplifies configuration, customizing the configuration can be a bit verbose.

Multi Tenancy

The Keycloak Spring Security adapter also supports multi tenancy.
Instead of injecting AdapterDeploymentContextFactoryBean with the path to keycloak.json you can inject an implementation of the KeycloakConfigResolver interface.
More details on how to implement the KeycloakConfigResolver can be found in Multi Tenancy.

Naming Security Roles

Spring Security, when using role-based authentication, requires that role names start with ROLE_.
For example, an administrator role must be declared in Keycloak as ROLE_ADMIN or similar, not simply ADMIN.

The class org.keycloak.adapters.springsecurity.authentication.KeycloakAuthenticationProvider supports an optional org.springframework.security.core.authority.mapping.GrantedAuthoritiesMapper which can be used to map roles coming from Keycloak to roles recognized by Spring Security.
Use, for example, org.springframework.security.core.authority.mapping.SimpleAuthorityMapper to insert the ROLE_ prefix and convert the role name to upper case.
The class is part of Spring Security Core module.

Client to Client Support

To simplify communication between clients, Keycloak provides an extension of Spring’s RestTemplate that handles bearer token authentication for you.
To enable this feature your security configuration must add the KeycloakRestTemplate bean.
Note that it must be scoped as a prototype to function correctly.

Avoid double Filter bean registration

Spring Boot attempts to eagerly register filter beans with the web application context.
Therefore, when running the Keycloak Spring Security adapter in a Spring Boot environment, it may be necessary to add two FilterRegistrationBeans to your security configuration to prevent the Keycloak filters from being registered twice.

2.1.9. Java Servlet Filter Adapter

If you are deploying your Java Servlet application on a platform where there is no Keycloak adapter you opt to use the servlet filter adapter.
This adapter works a bit differently than the other adapters. You do not define security constraints in web.xml.
Instead you define a filter mapping using the Keycloak servlet filter adapter to secure the url patterns you want to secure.

Backchannel logout works a bit differently than the standard adapters.
Instead of invalidating the HTTP session it marks the session id as logged out.
There’s no standard way to invalidate an HTTP session based on a session id.

In the snippet above there are two url-patterns.
/protected/* are the files we want protected, while the /keycloak/* url-pattern handles callbacks from the Keycloak server.

If you need to exclude some paths beneath the configured url-patterns you can use the Filter init-param keycloak.config.skipPattern to configure
a regular expression that describes a path-pattern for which the keycloak filter should immediately delegate to the filter-chain.
By default no skipPattern is configured.

Patterns are matched against the requestURI without the context-path. Given the context-path /myapp a request for /myapp/index.html will be matched with /index.html against the skip pattern.

2.1.10. JAAS plugin

It’s generally not needed to use JAAS for most of the applications, especially if they are HTTP based, and you should most likely choose one of our other adapters.
However, some applications and systems may still rely on pure legacy JAAS solution.
Keycloak provides two login modules to help in these situations.

The provided login modules are:

org.keycloak.adapters.jaas.DirectAccessGrantsLoginModule

This login module allows to authenticate with username/password from Keycloak.
It’s using Resource Owner Password Credentials flow to validate if the provided
username/password is valid. It’s useful for non-web based systems, which need to rely on JAAS and want to use Keycloak, but can’t use the standard browser
based flows due to their non-web nature. Example of such application could be messaging or SSH.

org.keycloak.adapters.jaas.BearerTokenLoginModule

This login module allows to authenticate with Keycloak access token passed to it through CallbackHandler as password.
It may be useful for example in case, when you have Keycloak access token from standard based authentication flow and your web application then
needs to talk to external non-web based system, which rely on JAAS. For example a messaging system.

Both modules use the following configuration properties:

keycloak-config-file

The location of the keycloak.json configuration file. The configuration file can either be located on the filesystem or on the classpath. If it’s located
on the classpath you need to prefix the location with classpath: (for example classpath:/path/keycloak.json).
This is REQUIRED.

role-principal-class

Configure alternative class for Role principals attached to JAAS Subject.
Default value is org.keycloak.adapters.jaas.RolePrincipal. Note: The class is required to have a constructor with a single String argument.

2.1.11. CLI / Desktop Applications

The KeycloakInstalled adapter supports a desktop and a manual
variant. The desktop variant uses the system browser
to gather the user credentials. The manual variant
reads the user credentials from STDIN.

How it works

To authenticate a user with the desktop variant the KeycloakInstalled
adapter opens a desktop browser window where a user uses the regular Keycloak
login pages to login when the loginDesktop() method is called on the KeycloakInstalled object.

The login page URL is opened with redirect parameter
that points to a local ServerSocket listening on a free ephemeral port
on localhost which is started by the adapter.

After a succesful login the KeycloakInstalled receives the authorization code
from the incoming HTTP request and performs the authorization code flow.
Once the code to token exchange is completed the ServerSocket is shutdown.

If the user already has an active Keycloak session then
the login form is not shown but the code to token exchange is continued,
which enables a smooth Web based SSO experience.

The client eventually receives the tokens (access_token, refresh_token,
id_token) which can then be used to call backend services.

The KeycloakInstalled adapter provides support for renewal of stale tokens.

Adapter Installation

Client Configuration

The application needs to be configured as a public OpenID Connect client with
Standard Flow Enabled and http://localhost:* as an allowed Valid Redirect URI.

Usage

The KeycloakInstalled adapter reads it’s configuration from
META-INF/keycloak.json on the classpath. Custom configurations
can be supplied with an InputStream or a KeycloakDeployment
through the KeycloakInstalled constructor.

In the example below, the client configuration for desktop-app
uses the following keycloak.json:

2.1.12. Security Context

The KeycloakSecurityContext interface is available if you need to access to the tokens directly. This could be useful if you want to retrieve additional
details from the token (such as user profile information) or you want to invoke a RESTful service that is protected by Keycloak.

In servlet environments it is available in secured invocations as an attribute in HttpServletRequest:

2.1.13. Error Handling

Keycloak has some error handling facilities for servlet based client adapters.
When an error is encountered in authentication, Keycloak will call HttpServletResponse.sendError().
You can set up an error-page within your web.xml file to handle the error however you want.
Keycloak can throw 400, 401, 403, and 500 errors.

Keycloak also sets a HttpServletRequest attribute that you can retrieve.
The attribute name is org.keycloak.adapters.spi.AuthenticationError, which should be casted to org.keycloak.adapters.OIDCAuthenticationError.

2.1.14. Logout

You can log out of a web application in multiple ways.
For Java EE servlet containers, you can call HttpServletRequest.logout(). For other browser applications, you can redirect the browser to
http://auth-server/auth/realms/{realm-name}/protocol/openid-connect/logout?redirect_uri=encodedRedirectUri, which logs you out if you have an SSO session with your browser.

2.1.15. Parameters Forwarding

The Keycloak initial authorization endpoint request has support for various parameters. Most of the parameters are described in
OIDC specification. Some parameters are added automatically by the adapter based
on the adapter configuration. However, there are also a few parameters that can be added on a per-invocation basis. When you open the secured application URI,
the particular parameter will be forwarded to the Keycloak authorization endpoint.

For example, if you request an offline token, then you can open the secured application URI with the scope parameter like:

http://myappserver/mysecuredapp?scope=offline_access

and the parameter scope=offline_access will be automatically forwarded to the Keycloak authorization endpoint.

The supported parameters are:

scope

prompt

max_age

login_hint

kc_idp_hint

Most of the parameters are described in the OIDC specification.
The only exception is parameter kc_idp_hint, which is specific to Keycloak and contains the name of the identity provider to automatically use.
For more information see the Identity Brokering section in Server Administration Guide.

2.1.16. Client Authentication

When a confidential OIDC client needs to send a backchannel request (for example, to exchange code for the token, or to refresh the token) it needs to authenticate against the Keycloak server. By default, there are two ways to authenticate the client: client ID and client secret, or client authentication with signed JWT.

Client ID and Client Secret

This is the traditional method described in the OAuth2 specification. The client has a secret, which needs to be known to both the adapter (application) and the Keycloak server.
You can generate the secret for a particular client in the Keycloak administration console, and then paste this secret into the keycloak.json file on the application side:

"credentials": {
"secret": "19666a4f-32dd-4049-b082-684c74115f28"
}

Client Authentication with Signed JWT

The client must have the private key and certificate. For Keycloak this is available through the traditional keystore file, which is either available on the client application’s classpath or somewhere on the file system.

Once the client application is started, it allows to download its public key in JWKS format using a URL such as http://myhost.com/myapp/k_jwks, assuming that http://myhost.com/myapp is the base URL of your client application. This URL can be used by Keycloak (see below).

During authentication, the client generates a JWT token and signs it with its private key and sends it to Keycloak in
the particular backchannel request (for example, code-to-token request) in the client_assertion parameter.

Keycloak must have the public key or certificate of the client so that it can verify the signature on JWT. In Keycloak you need to configure client credentials for your client. First you need to choose Signed JWT as the method of authenticating your client in the tab Credentials in administration console.
Then you can choose to either:

Configure the JWKS URL where Keycloak can download the client’s public keys. This can be a URL such as http://myhost.com/myapp/k_jwks (see details above). This option is the most flexible, since the client can rotate its keys anytime and Keycloak then always downloads new keys when needed without needing to change the configuration. More accurately, Keycloak downloads new keys when it sees the token signed by an unknown kid (Key ID).

Upload the client’s public key or certificate, either in PEM format, in JWK format, or from the keystore. With this option, the public key is hardcoded and must be changed when the client generates a new key pair.
You can even generate your own keystore from the Keycloak admininstration console if you don’t have your own available.
For more details on how to set up the Keycloak administration console see Server Administration Guide.

For set up on the adapter side you need to have something like this in your keycloak.json file:

With this configuration, the keystore file keystore-client.jks must be available on classpath in your WAR. If you do not use the prefix classpath:
you can point to any file on the file system where the client application is running.

For inspiration, you can take a look at the examples distribution into the main demo example into the product-portal application.

Add Your Own Client Authentication Method

You can add your own client authentication method as well. You will need to implement both client-side and server-side providers. For more details see the Authentication SPI section in Server Developer Guide.

2.1.17. Multi Tenancy

Multi Tenancy, in our context, means that a single target application (WAR) can be secured with multiple Keycloak realms. The realms can be located
one the same Keycloak instance or on different instances.

In practice, this means that the application needs to have multiple keycloak.json adapter configuration files.

You could have multiple instances of your WAR with different adapter configuration files deployed to different context-paths. However, this may be inconvenient
and you may also want to select the realm based on something else than context-path.

Keycloak makes it possible to have a custom config resolver so you can choose what adapter config is used for each request.

To achieve this first you need to create an implementation of org.keycloak.adapters.KeycloakConfigResolver. For example:

2.1.18. Application Clustering

This chapter is related to supporting clustered applications deployed to JBoss EAP, WildFly and JBoss AS.

There are a few options available depending on whether your application is:

Stateless or stateful

Distributable (replicated http session) or non-distributable

Relying on sticky sessions provided by load balancer

Hosted on same domain as Keycloak

Dealing with clustering is not quite as simple as for a regular application. Mainly due to the fact that both the browser and the server-side application
sends requests to Keycloak, so it’s not as simple as enabling sticky sessions on your load balancer.

Stateless token store

By default, the web application secured by Keycloak uses the HTTP session to store security context. This means that you either have to
enable sticky sessions or replicate the HTTP session.

As an alternative to storing the security context in the HTTP session the adapter can be configured to store this in a cookie instead. This is useful if you want
to make your application stateless or if you don’t want to store the security context in the HTTP session.

To use the cookie store for saving the security context, edit your applications WEB-INF/keycloak.json and add:

"token-store": "cookie"

The default value for token-store is session, which stores the security context in the HTTP session.

One limitation of using the cookie store is that the whole security context is passed in the cookie for every HTTP request. This may impact performance.

Another small limitation is limited support for Single-Sign Out. It works without issues if you init servlet logout (HttpServletRequest.logout) from the
application itself as the adapter will delete the KEYCLOAK_ADAPTER_STATE cookie. However, back-channel logout initialized from a different application isn’t
propagated by Keycloak to applications using cookie store. Hence it’s recommended to use a short value for the access token timeout (for example 1 minute).

Relative URI optimization

In deployment scenarios where Keycloak and the application is hosted on the same domain (through a reverse proxy or load balancer) it can be
convenient to use relative URI options in your client configuration.

With relative URIs the URI is resolved as relative to the URL used to access Keycloak.

For example if the URL to your application is https://acme.org/myapp and the URL to Keycloak is https://acme.org/auth, then you can use
the redirect-uri /myapp instead of https://acme.org/myapp.

Admin URL configuration

Admin URL for a particular client can be configured in the Keycloak Administration Console.
It’s used by the Keycloak server to send backend requests to the application for various tasks, like logout users or push revocation policies.

For example the way backchannel logout works is:

User sends logout request from one application

The application sends logout request to Keycloak

The Keycloak server invalidates the user session

The Keycloak server then sends a backchannel request to application with an admin url that are associated with the session

When an application receives the logout request it invalidates the corresponding HTTP session

If admin URL contains ${application.session.host} it will be replaced with the URL to the node associated with the HTTP session.

Registration of application nodes

The previous section describes how Keycloak can send logout request to node associated with a specific HTTP session.
However, in some cases admin may want to propagate admin tasks to all registered cluster nodes, not just one of them.
For example to push a new not before policy to the application or to logout all users from the application.

In this case Keycloak needs to be aware of all application cluster nodes, so it can send the event to all of them.
To achieve this, we support auto-discovery mechanism:

When a new application node joins the cluster, it sends a registration request to the Keycloak server

The request may be re-sent to Keycloak in configured periodic intervals

If the Keycloak server doesn’t receive a re-registration request within a specified timeout then it automatically unregisters the specific node

The node is also unregistered in Keycloak when it sends an unregistration request, which is usually during node shutdown or application undeployment.
This may not work properly for forced shutdown when undeployment listeners are not invoked, which results in the need for automatic unregistration

Sending startup registrations and periodic re-registration is disabled by default as it’s only required for some clustered applications.

To enable the feature edit the WEB-INF/keycloak.json file for your application and add:

"register-node-at-startup": true,
"register-node-period": 600,

This means the adapter will send the registration request on startup and re-register every 10 minutes.

In the Keycloak Administration Console you can specify the maximum node re-registration timeout (should be larger than register-node-period from
the adapter configuration). You can also manually add and remove cluster nodes in through the Adminstration Console, which is useful if you don’t want to rely
on the automatic registration feature or if you want to remove stale application nodes in the event your not using the automatic unregistration feature.

Refresh token in each request

By default the application adapter will only refresh the access token when it’s expired. However, you can also configure the adapter to refresh the token on every
request. This may have a performance impact as your application will send more requests to the Keycloak server.

To enable the feature edit the WEB-INF/keycloak.json file for your application and add:

"always-refresh-token": true

This may have a significant impact on performance. Only enable this feature if you can’t rely on backchannel messages to propagate logout and not before
policies. Another thing to consider is that by default access tokens has a short expiration so even if logout is not propagated the token will expire within
minutes of the logout.

2.2. Javascript Adapter

Keycloak comes with a client-side JavaScript library that can be used to secure HTML5/JavaScript applications. The JavaScript adapter has built-in support for Cordova applications.

The library can be retrieved directly from the Keycloak server at /auth/js/keycloak.js and is also distributed as a ZIP archive.

A best practice is to load the JavaScript adapter directly from Keycloak Server as it will automatically be updated when you upgrade the server. If you copy the adapter to your web application instead, make sure you upgrade the adapter only after you have upgraded the server.

One important thing to note about using client-side applications is that the client has to be a public client as there is no secure way to store client
credentials in a client-side application. This makes it very important to make sure the redirect URIs you have configured for the client are correct and as specific as possible.

To use the JavaScript adapter you must first create a client for your application in the Keycloak Administration Console. Make sure public
is selected for Access Type.

You also need to configure valid redirect URIs and valid web origins. Be as specific as possible as failing to do so may result in a security vulnerability.

Once the client is created click on the Installation tab select Keycloak OIDC JSON for Format Option then click Download. The downloaded
keycloak.json file should be hosted on your web server at the same location as your HTML pages.

Alternatively, you can skip the configuration file and manually configure the adapter.

By default to authenticate you need to call the login function. However, there are two options available to make the adapter automatically authenticate. You
can pass login-required or check-sso to the init function. login-required will authenticate the client if the user is logged-in to Keycloak
or display the login page if not. check-sso will only authenticate the client if the user is already logged-in, if the user is not logged-in the browser will be
redirected back to the application and remain unauthenticated.

To enable login-required set onLoad to login-required and pass to the init method:

keycloak.init({ onLoad: 'login-required' })

After the user is authenticated the application can make requests to RESTful services secured by Keycloak by including the bearer token in the
Authorization header. For example:

One thing to keep in mind is that the access token by default has a short life expiration so you may need to refresh the access token prior to sending the
request. You can do this by the updateToken method. The updateToken method returns a promise object which makes it easy to invoke the service only if the
token was successfully refreshed and for example display an error to the user if it wasn’t. For example:

2.2.1. Session Status iframe

By default, the JavaScript adapter creates a hidden iframe that is used to detect if a Single-Sign Out has occurred.
This does not require any network traffic, instead the status is retrieved by looking at a special status cookie.
This feature can be disabled by setting checkLoginIframe: false in the options passed to the init method.

You should not rely on looking at this cookie directly. It’s format can change and it’s also associated with the URL of the Keycloak server, not
your application.

2.2.2. Implicit and Hybrid Flow

With this flow the Keycloak server returns an authorization code, not an authentication token, to the application. The JavaScript adapter exchanges
the code for an access token and a refresh token after the browser is redirected back to the application.

Keycloak also supports the Implicit flow where an access token
is sent immediately after successful authentication with Keycloak. This may have better performance than standard flow, as there is no additional
request to exchange the code for tokens, but it has implications when the access token expires.

However, sending the access token in the URL fragment can be a security vulnerability. For example the token could be leaked through web server logs and or
browser history.

To enable implicit flow, you need to enable the Implicit Flow Enabled flag for the client in the Keycloak Administration Console.
You also need to pass the parameter flow with value implicit to init method:

keycloak.init({ flow: 'implicit' })

One thing to note is that only an access token is provided and there is no refresh token. This means that once the access token has expired the application
has to do the redirect to the Keycloak again to obtain a new access token.

This requires the client to have both the Standard Flow Enabled and Implicit Flow Enabled flags enabled in the admin console.
The Keycloak server will then send both the code and tokens to your application.
The access token can be used immediately while the code can be exchanged for access and refresh tokens.
Similar to the implicit flow, the hybrid flow is good for performance because the access token is available immediately.
But, the token is still sent in the URL, and the security vulnerability mentioned earlier may still apply.

One advantage in the Hybrid flow is that the refresh token is made available to the application.

For the Hybrid flow, you need to pass the parameter flow with value hybrid to the init method:

keycloak.init({ flow: 'hybrid' })

2.2.3. Earlier Browsers

The JavaScript adapter depends on Base64 (window.btoa and window.atob) and HTML5 History API.
If you need to support browsers that do not have these available (for example, IE9) you need to add polyfillers.

Properties

The base64 encoded token that can be sent in the Authorization header in requests to services.

tokenParsed

The parsed token as a JavaScript object.

subject

The user id.

idToken

The base64 encoded ID token.

idTokenParsed

The parsed id token as a JavaScript object.

realmAccess

The realm roles associated with the token.

resourceAccess

The resource roles associated with the token.

refreshToken

The base64 encoded refresh token that can be used to retrieve a new token.

refreshTokenParsed

The parsed refresh token as a JavaScript object.

timeSkew

The estimated time difference between the browser time and the Keycloak server in seconds. This value is just an estimation, but is accurate
enough when determining if a token is expired or not.

responseMode

Response mode passed in init (default value is fragment).

flow

Flow passed in init.

responseType

Response type sent to Keycloak with login requests. This is determined based on the flow value used during initialization, but can be overridden by setting this value.

Methods

init(options)

Called to initialize the adapter.

Options is an Object, where:

onLoad - Specifies an action to do on load. Supported values are 'login-required' or 'check-sso'.

token - Set an initial value for the token.

refreshToken - Set an initial value for the refresh token.

idToken - Set an initial value for the id token (only together with token or refreshToken).

timeSkew - Set an initial value for skew between local time and Keycloak server in seconds (only together with token or refreshToken).

checkLoginIframe - Set to enable/disable monitoring login state (default is true).

checkLoginIframeInterval - Set the interval to check login state (default is 5 seconds).

responseMode - Set the OpenID Connect response mode send to Keycloak server at login request. Valid values are query or fragment . Default value is fragment, which means that after successful authentication will Keycloak redirect to javascript application with OpenID Connect parameters added in URL fragment. This is generally safer and recommended over query.

login(options)

Redirects to login form on (options is an optional object with redirectUri and/or prompt fields).

Options is an Object, where:

redirectUri - Specifies the uri to redirect to after login.

prompt - By default the login screen is displayed if the user is not logged-in to Keycloak. To only authenticate to the application if the user is already logged-in and not display the login page if the user is not logged-in, set this option to none. To always require re-authentication and ignore SSO, set this option to login .

maxAge - Used just if user is already authenticated. Specifies maximum time since the authentication of user happened. If user is already authenticated for longer time than maxAge, the SSO is ignored and he will need to re-authenticate again.

loginHint - Used to pre-fill the username/email field on the login form.

action - If value is 'register' then user is redirected to registration page, otherwise to login page.

locale - Specifies the desired locale for the UI.

createLoginUrl(options)

Returns the URL to login form on (options is an optional object with redirectUri and/or prompt fields).

Options is an Object, which supports same options like the function login .

isTokenExpired(minValidity)

Returns true if the token has less than minValidity seconds left before it expires (minValidity is optional, if not specified 0 is used).

updateToken(minValidity)

If the token expires within minValidity seconds (minValidity is optional, if not specified 5 is used) the token is refreshed.
If the session status iframe is enabled, the session status is also checked.

Returns promise to set functions that can be invoked if the token is still valid, or if the token is no longer valid.
For example:

keycloak.updateToken(5).success(function(refreshed) {
if (refreshed) {
alert('Token was successfully refreshed');
} else {
alert('Token is still valid');
}
}).error(function() {
alert('Failed to refresh the token, or the session has expired');
});

clearToken()

Clear authentication state, including tokens.
This can be useful if application has detected the session was expired, for example if updating token fails.

Invoking this results in onAuthLogout callback listener being invoked.

Callback Events

The adapter supports setting callback listeners for certain events.

For example:

keycloak.onAuthSuccess = function() { alert('authenticated'); }

The available events are:

onReady(authenticated) - Called when the adapter is initialized.

onAuthSuccess - Called when a user is successfully authenticated.

onAuthError - Called if there was an error during authentication.

onAuthRefreshSuccess - Called when the token is refreshed.

onAuthRefreshError - Called if there was an error while trying to refresh the token.

onAuthLogout - Called if the user is logged out (will only be called if the session status iframe is enabled, or in Cordova mode).

onTokenExpired - Called when the access token is expired. If a refresh token is available the token can be refreshed with updateToken, or in cases where it is not (that is, with implicit flow) you can redirect to login screen to obtain a new access token.

2.3. Node.js Adapter

Keycloak provides a Node.js adapter built on top of Connect to protect server-side JavaScript apps — the goal was to be flexible enough to integrate with frameworks like Express.js.

To use the Node.js adapter, first you must create a client for your application in the Keycloak Administration Console. The adapter supports public, confidential, and bearer-only access type. Which one to choose depends on the use-case scenario.

Once the client is created click the Installation tab, select Keycloak OIDC JSON for Format Option, and then click Download. The downloaded keycloak.json file should be at the root folder of your project.

By default, this will locate a file named keycloak.json alongside
the main executable of your application to initialize keycloak-specific
settings (public key, realm name, various URLs). The keycloak.json file
is obtained from the Keycloak Admin Console.

Instantiation with this method results in all of the reasonable defaults
being used. As alternative, it’s also possible to provide a configuration
object, rather than the keycloak.json file:

If you want to use web sessions to manage
server-side state for authentication, you need to initialize the
Keycloak(…​) with at least a store parameter, passing in the actual
session store that express-session is using.

2.3.5. Additional URLs

Explicit user-triggered logout

By default, the middleware catches calls to /logout to send the user through a
Keycloak-centric logout workflow. This can be changed by specifying a logout
configuration parameter to the middleware() call:

app.use( keycloak.middleware( { logout: '/logoff' } ));

Keycloak Admin Callbacks

Also, the middleware supports callbacks from the Keycloak console to log out a single
session or all sessions. By default, these type of admin callbacks occur relative
to the root URL of / but can be changed by providing an admin parameter
to the middleware() call:

app.use( keycloak.middleware( { admin: '/callbacks' } );

2.4. Other OpenID Connect Libraries

Keycloak can be secured by supplied adapters that are usually easier to use and provide better integration with Keycloak. However, if an adapter is not available for your programming language, framework, or platform you might opt to use a generic OpenID Connect Resource Provider (RP) library instead. This chapter describes details specific to Keycloak and does not contain specific protocol details. For more information see the OpenID Connect specifications and OAuth2 specification.

2.4.1. Endpoints

The most important endpoint to understand is the well-known configuration endpoint. It lists endpoints and other configuration options relevant to the OpenID Connect implementation in Keycloak. The endpoint is:

/realms/{realm-name}/.well-known/openid-configuration

To obtain the full URL, add the base URL for Keycloak and replace {realm-name} with the name of your realm. For example:

Token Endpoint

/realms/{realm-name}/protocol/openid-connect/token

The token endpoint is used to obtain tokens. Tokens can either be obtained by exchanging an authorization code or by supplying credentials directly depending on what flow is used.
The token endpoint is also used to obtain new access tokens when they expire.

For more details see the Token Endpoint section in the OpenID Connect specification.

Userinfo Endpoint

/realms/{realm-name}/protocol/openid-connect/userinfo

The userinfo endpoint returns standard claims about the authenticated user, and is protected by a bearer token.

For more details see the Userinfo Endpoint section in the OpenID Connect specification.

Logout Endpoint

/realms/{realm-name}/protocol/openid-connect/logout

The logout endpoint logs out the authenticated user.

The user agent can be redirected to the endpoint, in which case the active user session is logged out. Afterward the user agent is redirected back to the application.

The endpoint can also be invoked directly by the application. To invoke this endpoint directly the refresh token needs to be included as well as the credentials required to authenticate the client.

Certificate Endpoint

/realms/{realm-name}/protocol/openid-connect/certs

The certificate endpoint returns the public keys enabled by the realm, encoded as a JSON Web Key (JWK). Depending on the realm settings there can be one or more keys enabled for verifying tokens. For more information see the Server Administration Guide and the JSON Web Key specification.

Introspection Endpoint

/realms/{realm-name}/protocol/openid-connect/token/introspect

The introspection endpoint is used to retrieve the active state of a token. It can only be invoked by confidential clients.

2.4.2. Flows

Authorization Code

The Authorization Code flow redirects the user agent to Keycloak. Once the user has successfully authenticated with Keycloak an
Authorization Code is created and the user agent is redirected back to the application. The application then uses the authorization code along with its
credentials to obtain an Access Token, Refresh Token and ID Token from Keycloak.

The flow is targeted towards web applications, but is also recommended for native applications, including mobile applications, where it is possible to embed
a user agent.

Implicit

The Implicit flow redirects works similarly to the Authorization Code flow, but instead of returning a Authorization Code the Access Token and ID Token is
returned. This reduces the need for the extra invocation to exchange the Authorization Code for an Access Token. However, it does not include a Refresh
Token. This results in the need to either permit Access Tokens with a long expiration, which is problematic as it’s very hard to invalidate these. Or
requires a new redirect to obtain new Access Token once the initial Access Token has expired. The Implicit flow is useful if the application only wants to
authenticate the user and deals with logout itself.

There’s also a Hybrid flow where both the Access Token and an Authorization Code is returned.

One thing to note is that both the Implicit flow and Hybrid flow has potential security risks as the Access Token may be leaked through web server logs and
browser history. This is somewhat mitigated by using short expiration for Access Tokens.

For more details refer to the Implicit Flow in the OpenID Connect specification.

Resource Owner Password Credentials

Resource Owner Password Credentials, referred to as Direct Grant in Keycloak, allows exchanging user credentials for tokens. It’s not recommended
to use this flow unless you absolutely need to. Examples where this could be useful are legacy applications and command-line interfaces.

Client Credentials

Client Credentials is used when clients (applications and services) wants to obtain access on behalf of themselves rather than on behalf of a user. This can
for example be useful for background services that applies changes to the system in general rather than for a specific user.

Keycloak provides support for clients to authenticate either with a secret or with public/private keys.

This flow is not included in OpenID Connect, but is a part of the OAuth 2.0 specification.

2.4.3. Redirect URIs

When using the redirect based flows it’s important to use valid redirect uris for your clients. The redirect uris should be as specific as possible. This
especially applies to client-side (public clients) applications. Failing to do so could result in:

Open redirects - this can allow attackers to create spoof links that looks like they are coming from your domain

Unauthorized entry - when users are already authenticated with Keycloak an attacker can use a public client where redirect uris have not be configured correctly to gain access by redirecting the user without the users knowledge

In production for web applications always use https for all redirect URIs. Do not allow redirects to http.

There’s also a few special redirect URIs:

http://localhost

This redirect URI is useful for native applications and allows the native application to create a web server on a random port that can be used to obtain the
authorization code. This redirect uri allows any port.

urn:ietf:wg:oauth:2.0:oob

If its not possible to start a web server in the client (or a browser is not available) it is possible to use the special urn:ietf:wg:oauth:2.0:oob redirect uri.
When this redirect uri is used Keycloak displays a page with the code in the title and in a box on the page.
The application can either detect that the browser title has changed, or the user can copy/paste the code manually to the application.
With this redirect uri it is also possible for a user to use a different device to obtain a code to paste back to the application.

2.4.4. mod_auth_openidc Apache HTTPD Module

The mod_auth_openidc is an Apache HTTP plugin for OpenID Connect. If your language/environment supports using Apache HTTPD
as a proxy, then you can use mod_auth_openidc to secure your web application with OpenID Connect. Configuration of this module
is beyond the scope of this document. Please see the mod_auth_openidc Github repo for more details on configuration.

Some of these configuration switches may be adapter specific and some are common across all adapters.
For Java adapters you can use ${…​} enclosure as System property replacement.
For example ${jboss.server.config.dir}.

This is the identifier for this client.
The IdP needs this value to determine who the client is that is communicating with it. This setting is REQUIRED.

sslPolicy

This is the SSL policy the adapter will enforce.
Valid values are: ALL, EXTERNAL, and NONE.
For ALL, all requests must come in via HTTPS.
For EXTERNAL, only non-private IP addresses must come over the wire via HTTPS.
For NONE, no requests are required to come over via HTTPS.
This setting is OPTIONAL. Default value is EXTERNAL.

nameIDPolicyFormat

SAML clients can request a specific NameID Subject format.
Fill in this value if you want a specific format.
It must be a standard SAML format identifier: urn:oasis:names:tc:SAML:2.0:nameid-format:transient.
This setting is OPTIONAL.
By default, no special format is requested.

forceAuthentication

SAML clients can request that a user is re-authenticated even if they are already logged in at the IdP.
Set this to true to enable. This setting is OPTIONAL.
Default value is false.

isPassive

SAML clients can request that a user is never asked to authenticate even if they are not logged in at the IdP.
Set this to true if you want this.
Do not use together with forceAuthentication as they are opposite. This setting is OPTIONAL.
Default value is false.

turnOffChangeSessionIdOnLogin

The session ID is changed by default on a successful login on some platforms to plug a security attack vector.
Change this to true to disable this. It is recommended you do not turn it off.
Default value is false.

autodetectBearerOnly

This should be set to true if your application serves both a web application and web services (e.g. SOAP or REST).
It allows you to redirect unauthenticated users of the web application to the Keycloak login page,
but send an HTTP 401 status code to unauthenticated SOAP or REST clients instead as they would not understand a redirect to the login page.
Keycloak auto-detects SOAP or REST clients based on typical headers like X-Requested-With, SOAPAction or Accept.
The default value is false.

Service Provider Keys and Key Elements

If the IdP requires that the client application (or SP) sign all of its requests and/or if the IdP will encrypt assertions, you must define the keys used to do this.
For client-signed documents you must define both the private and public key or certificate that is used to sign documents.
For encryption, you only have to define the private key that is used to decrypt it.

There are two ways to describe your keys.
They can be stored within a Java KeyStore or you can copy/paste the keys directly within keycloak-saml.xml in the PEM format.

<Keys><Keysigning="true">
...
</Key></Keys>

The Key element has two optional attributes signing and encryption.
When set to true these tell the adapter what the key will be used for.
If both attributes are set to true, then the key will be used for both signing documents and decrypting encrypted assertions.
You must set at least one of these attributes to true.

KeyStore element

Within the Key element you can load your keys and certificates from a Java Keystore. This is declared within
a KeyStore element.

Here are the XML config attributes that are defined with the KeyStore element.

file

File path to the key store. This option is OPTIONAL. The file or resource attribute must be set.

resource

WAR resource path to the KeyStore.
This is a path used in method call to ServletContext.getResourceAsStream(). This option is OPTIONAL. The file or resource attribute must be set.

password

The password of the KeyStore. This option is REQUIRED.

If you are defining keys that the SP will use to sign document, you must also specify references to your private keys
and certificates within the Java KeyStore.
The PrivateKey and Certificate elements in the above example define an alias that points to the key or cert
within the keystore. Keystores require an additional password to access private keys.
In the PrivateKey element you must define this password within a password attribute.

Key PEMS

Within the Key element you declare your keys and certificates directly using the sub elements
PrivateKeyPem, PublicKeyPem, and CertificatePem.
The values contained in these elements must conform to the PEM key format.
You usually use this option if you are generating keys using openssl or similar command line tool.

SP PrincipalNameMapping element

This element is optional.
When creating a Java Principal object that you obtain from methods such as HttpServletRequest.getUserPrincipal(), you can define what name is returned by the Principal.getName() method.

The policy attribute defines the policy used to populate this value.
The possible values for this attribute are:

FROM_NAME_ID

This policy just uses whatever the SAML subject value is. This is the default setting

FROM_ATTRIBUTE

This will pull the value from one of the attributes declared in the SAML assertion received from the server.
You’ll need to specify the name of the SAML assertion attribute to use within the attribute XML attribute.

RoleIdentifiers Element

The RoleIdentifiers element defines what SAML attributes within the assertion received from the user should be used
as role identifiers within the Java EE Security Context for the user.

By default Role attribute values are converted to Java EE roles.
Some IdPs send roles using a member or memberOf attribute assertion.
You can define one or more Attribute elements to specify which SAML attributes must be converted into roles.

IDP Element

Everything in the IDP element describes the settings for the identity provider (authentication server) the SP is communicating with.

Here are the attribute config options you can specify within the IDP element declaration.

entityID

This is the issuer ID of the IDP. This setting is REQUIRED.

signaturesRequired

If set to true, the client adapter will sign every document it sends to the IDP.
Also, the client will expect that the IDP will be signing any documents sent to it.
This switch sets the default for all request and response types, but you will see later that you have some fine grain control over this.
This setting is OPTIONAL and will default to false.

signatureAlgorithm

This is the signature algorithm that the IDP expects signed documents to use.
Allowed values are: RSA_SHA1, RSA_SHA256, RSA_SHA512, and DSA_SHA1.
This setting is OPTIONAL
and defaults to RSA_SHA256.

signatureCanonicalizationMethod

This is the signature canonicalization method that the IDP expects signed documents to use. This setting is OPTIONAL.
The default value is http://www.w3.org/2001/10/xml-exc-c14n# and should be good for most IDPs.

IDP SingleSignOnService sub element

The SingleSignOnService sub element defines the login SAML endpoint of the IDP.
The client adapter will send requests
to the IDP formatted via the settings within this element when it wants to login.

Should the client sign authn requests? This setting is OPTIONAL.
Defaults to whatever the IDP signaturesRequired element value is.

validateResponseSignature

Should the client expect the IDP to sign the assertion response document sent back from an auhtn request?
This setting OPTIONAL. Defaults to whatever the IDP signaturesRequired element value is.

requestBinding

This is the SAML binding type used for communicating with the IDP. This setting is OPTIONAL.
The default value is POST, but you can set it to REDIRECT as well.

responseBinding

SAML allows the client to request what binding type it wants authn responses to use.
The values of this can be POST or REDIRECT. This setting is OPTIONAL.
The default is that the client will not request a specific binding type for responses.

assertionConsumerServiceUrl

URL of the assertion consumer service (ACS) where the IDP login service should send responses to.
This setting is OPTIONAL. By default it is unset, relying on the configuration in the IdP.
When set, it must end in /saml, e.g. http://sp.domain.com/my/endpoint/for/saml. The value
of this property is sent in AssertionConsumerServiceURL attribute of SAML AuthnRequest message.
This property is typically accompanied by the responseBinding attribute.

bindingUrl

This is the URL for the IDP login service that the client will send requests to. This setting is REQUIRED.

IDP SingleLogoutService sub element

The SingleLogoutService sub element defines the logout SAML endpoint of the IDP. The client adapter will send requests
to the IDP formatted via the settings within this element when it wants to logout.

Should the client sign logout requests it makes to the IDP? This setting is OPTIONAL.
Defaults to whatever the IDP signaturesRequired element value is.

signResponse

Should the client sign logout responses it sends to the IDP requests? This setting is OPTIONAL.
Defaults to whatever the IDP signaturesRequired element value is.

validateRequestSignature

Should the client expect signed logout request documents from the IDP? This setting is OPTIONAL. Defaults to whatever the IDP signaturesRequired element value is.

validateResponseSignature

Should the client expect signed logout response documents from the IDP? This setting is OPTIONAL. Defaults to whatever the IDP signaturesRequired element value is.

requestBinding

This is the SAML binding type used for communicating SAML requests to the IDP. This setting is OPTIONAL.
The default value is POST, but you can set it to REDIRECT as well.

responseBinding

This is the SAML binding type used for communicating SAML responses to the IDP. The values of this can be POST or REDIRECT. This setting is OPTIONAL.
The default value is POST, but you can set it to REDIRECT as well.

postBindingUrl

This is the URL for the IDP’s logout service when using the POST binding. This setting is REQUIRED if using the POST binding.

redirectBindingUrl

This is the URL for the IDP’s logout service when using the REDIRECT binding. This setting is REQUIRED if using the REDIRECT binding.

IDP Keys sub element

The Keys sub element of IDP is only used to define the certificate or public key to use to verify documents signed by the IDP.
It is defined in the same way as the SP’s Keys element.
But again, you only have to define one certificate or public key reference. Note that, if both IDP and SP are realized by
Keycloak server and adapter, respectively, there is no need to specify the keys for signature validation, see below.

It is possible to configure SP to obtain public keys for IDP signature validation
from published certificates automatically, provided both SP and IDP are
implemented by Keycloak.
This is done by removing all declarations of signature validation keys in Keys
sub element. If the Keys sub element would then remain empty, it can be omitted
completely. The keys are then automatically obtained by SP from SAML descriptor,
location of which is derived from SAML endpoint URL specified in the
IDP SingleSignOnService sub element.
Settings of the HTTP client that is used for SAML descriptor retrieval usually
needs no additional configuration, however it can be configured in the
IDP HttpClient sub element.

It is also possible to specify multiple keys for signature verification. This is done by declaring multiple Key elements
within Keys sub element that have signing attribute set to true.
This is useful for example in situation when the IDP signing keys are rotated: There is
usually a transition period when new SAML protocol messages and assertions are signed
with the new key but those signed by previous key should still be accepted.

It is not possible to configure Keycloak to both obtain the keys
for signature verification automatically and define additional static signature
verification keys.

IDP HttpClient sub element

The HttpClient optional sub element defines the properties of HTTP client used
for automatic obtaining of certificates containing public keys for IDP signature
verification via SAML descriptor of the IDP when
enabled.

Adapters will make separate HTTP invocations to the Keycloak server to turn an access code into an access token.
This config option defines how many connections to the Keycloak server should be pooled.
This is OPTIONAL.
The default value is 10.

disableTrustManager

If the Keycloak server requires HTTPS and this config option is set to true you do not have to specify a truststore.
This setting should only be used during development and never in production as it will disable verification of SSL certificates.
This is OPTIONAL.
The default value is false.

allowAnyHostname

If the Keycloak server requires HTTPS and this config option is set to true
the Keycloak server’s certificate is validated via the truststore,
but host name validation is not done.
This setting should only be used during development and never in production
as it will partly disable verification of SSL certificates.
This seting may be useful in test environments. This is OPTIONAL.
The default value is false.

truststore

The value is the file path to a keystore file.
If you prefix the path with classpath:, then the truststore will be obtained from the deployment’s classpath instead.
Used for outgoing HTTPS communications to the Keycloak server.
Client making HTTPS requests need a way to verify the host of the server they are talking to.
This is what the trustore does.
The keystore contains one or more trusted host certificates or certificate authorities.
You can create this truststore by extracting the public certificate of the Keycloak server’s SSL keystore.
This is REQUIRED unless disableTrustManager is true.

truststorePassword

Password for the truststore keystore.
This is REQUIRED if truststore is set and the truststore requires a password.

clientKeystore

This is the file path to a keystore file.
This keystore contains client certificate for two-way SSL when the adapter makes HTTPS requests to the Keycloak server.
This is OPTIONAL.

clientKeystorePassword

Password for the client keystore and for the client’s key.
This is REQUIRED if clientKeystore is set.

proxyUrl

URL to HTTP proxy to use for HTTP connections.
This is OPTIONAL.

3.1.2. JBoss EAP/Wildfly Adapter

To be able to secure WAR apps deployed on JBoss EAP or Wildfly, you must install and configure the Keycloak SAML Adapter Subsystem.

You then provide a keycloak config, /WEB-INF/keycloak-saml.xml file in your WAR and change the auth-method to KEYCLOAK-SAML within web.xml.
Both methods are described in this section.

The keycloak security domain should be used with EJBs and other components when you need the security context created
in the secured web tier to be propagated to the EJBs (other EE component) you are invoking.
Otherwise this configuration is optional.

We hope to improve our integration in the future so that you don’t have to specify the
@SecurityDomain annotation when you want to propagate a keycloak security context to the EJB tier.

JBoss SSO

WildFly has built-in support for single sign-on for web applications deployed to the same WildFly
instance. This should not be enabled when using Keycloak.

Per WAR Configuration

This section describes how to secure a WAR directly by adding config and editing files within your WAR package.

The first thing you must do is create a keycloak-saml.xml adapter config file within the WEB-INF directory of your WAR.
The format of this config file is described in the General Adapter Config section.

Next you must set the auth-method to KEYCLOAK-SAML in web.xml.
You also have to use standard servlet security to specify role-base constraints on your URLs.
Here’s an example web.xml file:

Securing WARs via Keycloak SAML Subsystem

You do not have to crack open a WAR to secure it with Keycloak.
Alternatively, you can externally secure it via the Keycloak SAML Adapter Subsystem.
While you don’t have to specify KEYCLOAK-SAML as an auth-method, you still have to define the security-constraints in web.xml.
You do not, however, have to create a WEB-INF/keycloak-saml.xml file.
This metadata is instead defined within the XML in your server’s domain.xml or standalone.xml subsystem configuration section.

The secure-deploymentname attribute identifies the WAR you want to secure.
Its value is the module-name defined in web.xml with .war appended.
The rest of the configuration uses the same XML syntax as keycloak-saml.xml configuration defined in General Adapter Config.

3.1.3. Tomcat SAML adapters

To be able to secure WAR apps deployed on Tomcat 6, 7 and 8 you must install the Keycloak Tomcat 6, 7 or 8 SAML adapter into your Tomcat installation.
You then have to provide some extra configuration in each WAR you deploy to Tomcat.
Let’s go over these steps.

Adapter Installation

Adapters are no longer included with the appliance or war distribution.
Each adapter is a separate download on the Keycloak download site.
They are also available as a maven artifact.

You must unzip the adapter distro into Tomcat’s lib/ directory.
Including adapter’s jars within your WEB-INF/lib directory will not work! The Keycloak SAML adapter is implemented as
a Valve and valve code must reside in Tomcat’s main lib/ directory.

3.1.4. Jetty SAML Adapters

To be able to secure WAR apps deployed on Jetty you must install the Keycloak Jetty 9.x or 8.x SAML adapter into your Jetty installation.
You then have to provide some extra configuration in each WAR you deploy to Jetty.
Let’s go over these steps.

Jetty 9 Adapter Installation

Keycloak has a separate SAML adapter for Jetty 9.x.
You then have to provide some extra configuration in each WAR you deploy to Jetty.
Let’s go over these steps.

Adapters are no longer included with the appliance or war distribution. Each adapter is a separate download on the Keycloak download site.
They are also available as a maven artifact.

You must unzip the Jetty 9.x distro into Jetty 9.x’s root directory.
Including adapter’s jars within your WEB-INF/lib directory will not work!

$ cd $JETTY_HOME
$ unzip keycloak-saml-jetty92-adapter-dist.zip

Next, you will have to enable the keycloak module for your jetty.base.

Jetty 8 Adapter Installation

Keycloak has a separate SAML adapter for Jetty 8.1.x that you will have to install into your Jetty installation.
You then have to provide some extra configuration in each WAR you deploy to Jetty.
Let’s go over these steps.

Adapters are no longer included with the appliance or war distribution. Each adapter is a separate download on the Keycloak download site.
They are also available as a maven artifact.

You must unzip the Jetty 8.1.x distro into Jetty 8.1.x’s root directory.
Including adapter’s jars within your WEB-INF/lib directory will not work!

$ cd $JETTY_HOME
$ unzip keycloak-saml-jetty81-adapter-dist.zip

Next, you will have to enable the keycloak option.
Edit start.ini and add keycloak to the options

#===========================================================
# Start classpath OPTIONS.
# These control what classes are on the classpath
# for a full listing do
# java -jar start.jar --list-options
#-----------------------------------------------------------
OPTIONS=Server,jsp,jmx,resources,websocket,ext,plus,annotations,keycloak

Jetty 8 Per WAR Configuration

3.1.5. Java Servlet Filter Adapter

If you want to use SAML with a Java servlet application that doesn’t have an adapter for that servlet platform, you can
opt to use the servlet filter adapter that Keycloak has.
This adapter works a little differently than the other adapters.
You still have to specify a /WEB-INF/keycloak-saml.xml file as defined in
the General Adapter Config section, but
you do not define security constraints in web.xml.
Instead you define a filter mapping using the Keycloak servlet filter adapter to secure the url patterns you want to secure.

Backchannel logout works a bit differently than the standard adapters.
Instead of invalidating the http session it instead marks the session ID as logged out.
There’s just no way of arbitrarily invalidating an http session based on a session ID.

Backchannel logout does not currently work when you have a clustered application that uses the SAML filter.

3.1.6. Registering with an Identity Provider

For each servlet-based adapter, the endpoint you register for the assert consumer service URL and and single logout service
must be the base URL of your servlet application with /saml appended to it, that is, https://example.com/contextPath/saml.

3.1.7. Logout

There are multiple ways you can logout from a web application.
For Java EE servlet containers, you can call HttpServletRequest.logout(). For any other browser application, you can point
the browser at any url of your web application that has a security constraint and pass in a query parameter GLO, i.e. http://myapp?GLO=true.
This will log you out if you have an SSO session with your browser.

Logout in Clustered Environment

Internally, the SAML adapter stores a mapping between the SAML session index, principal name (when known), and HTTP session ID.
This mapping can be maintained in JBoss application server family (Wildfly 10/11, EAP 6/7) across cluster for distributable
applications. As a precondition, the HTTP sessions need to be distributed across cluster (i.e. application is marked with
<distributable/> tag in application’s web.xml).

To enable the functionality, add the following section to your /WEB_INF/web.xml file:

If the session cache of the deployment is named deployment-cache, the cache used for SAML mapping will be named
as deployment-cache.ssoCache. The name of the cache can be overridden by a context parameter
keycloak.sessionIdMapperUpdater.infinispan.cacheName. The cache container containing the cache will be the same as
the one containing the deployment session cache, but can be overridden by a context parameter
keycloak.sessionIdMapperUpdater.infinispan.containerName.

By default, the configuration of the SAML mapping cache will be derived from session cache. The configuration can
be manually overridden in cache configuration section of the server just the same as other caches.

Currently, to provide reliable service, it is recommended to use replicated cache for the SAML session cache.
Using distributed cache may lead to results where the SAML logout request would land to a node with no access
to SAML session index to HTTP session mapping which would lead to unsuccessful logout.

Logout in Cross DC Scenario

The cross DC scenario only applies to Wildfly 10 and higher, and EAP 7 and higher.

Special handling is needed for handling sessions that span multiple data centers. Imagine the following scenario:

The cache from previous item has to be added as a remote store for the respective SAML session cache.

Once remote store is found to be present on SAML session cache during deployment, it is watched for changes
and the local SAML session cache is updated accordingly.

3.1.8. Obtaining Assertion Attributes

After a successful SAML login, your application code may want to obtain attribute values passed with the SAML assertion.
HttpServletRequest.getUserPrincipal() returns a Principal object that you can typecast into a Keycloak specific class
called org.keycloak.adapters.saml.SamlPrincipal.
This object allows you to look at the raw assertion and also has convenience functions to look up attribute values.

3.1.9. Error Handling

Keycloak has some error handling facilities for servlet based client adapters.
When an error is encountered in authentication, the client adapter will call HttpServletResponse.sendError().
You can set up an error-page within your web.xml file to handle the error however you want.
The client adapter can throw 400, 401, 403, and 500 errors.

The client adapter also sets an HttpServletRequest attribute that you can retrieve.
The attribute name is org.keycloak.adapters.spi.AuthenticationError.
Typecast this object to: org.keycloak.adapters.saml.SamlAuthenticationError.
This class can tell you exactly what happened.
If this attribute is not set, then the adapter was not responsible for the error code.

3.1.10. Troubleshooting

The best way to troubleshoot problems is to turn on debugging for SAML in both the client adapter and Keycloak Server. Using your logging framework, set the log level to DEBUG for the org.keycloak.saml package. Turning this on allows you to see the SAML requests and response documents being sent to and from the server.
==== Migration from older versions

Migrating to 1.9.0

SAML SP Client Adapter Changes

Keycloak SAML SP Client Adapter now requires a specific endpoint, /saml to be registered with your IdP.
The SamlFilter must also be bound to /saml in addition to any other binding it has.
This had to be done because SAML POST binding would eat the request input stream and this would be really bad for clients that relied on it.

3.2. mod_auth_mellon Apache HTTPD Module

The mod_auth_mellon module is an Apache HTTPD plugin for SAML. If your language/environment supports using Apache HTTPD as a proxy, then you can use mod_auth_mellon to secure your web application with SAML. For more details on this module see the mod_auth_mellon Github repo.

To configure mod_auth_mellon you’ll need:

An Identity Provider (IdP) entity descriptor XML file, which describes the connection to Keycloak or another SAML IdP

An SP entity descriptor XML file, which describes the SAML connections and configuration for the application you are securing.

A private key PEM file, which is a text file in the PEM format that defines the private key the application uses to sign documents.

A certificate PEM file, which is a text file that defines the certificate for your application.

mod_auth_mellon-specific Apache HTTPD module configuration.

If you have already defined and registered the client application within a realm on the Keycloak application server, Keycloak can generate all the files you need except the Apache HTTPD module configuration.

To generate the Apache HTTPD module configuration, complete the following steps:

Click Download to download a zip file that contains the XML descriptor and PEM files you need.

3.2.1. Configuring mod_auth_mellon with Keycloak

There are two hosts involved:

The host on which Keycloak is running, which will be referred to as $idp_host because Keycloak is a SAML identity provider (IdP).

The host on which the web application is running, which will be referred to as $sp_host. In SAML an application using an IdP is called a service provider (SP).

All of the following steps need to performed on $sp_host with root privileges.

Installing the Packages

To install the necessary packages, you will need:

Apache Web Server (httpd)

Mellon SAML SP add-on module for Apache

Tools to create X509 certificates

To install the necessary packages, run this command:

yum install httpd mod_auth_mellon mod_ssl openssl

Creating a Configuration Directory for Apache SAML

It is advisable to keep configuration files related to Apache’s use of SAML in one location.

Create a new directory named saml2 located under the Apache configuration root /etc/httpd:

mkdir /etc/httpd/saml2

Configuring the Mellon Service Provider

Configuration files for Apache add-on modules are located in the /etc/httpd/conf.d directory and have a file name extension of .conf. You need to create the /etc/httpd/conf.d/mellon.conf file and place Mellon’s configuration directives in it.

Mellon’s configuration directives can roughly be broken down into two classes of information:

Which URLs to protect with SAML authentication

What SAML parameters will be used when a protected URL is referenced.

Apache configuration directives typically follow a hierarchical tree structure in the URL space, which are known as locations. You need to specify one or more URL locations for Mellon to protect. You have flexibility in how you add the configuration parameters that apply to each location. You can either add all the necessary parameters to the location block or you can add Mellon parameters to a common location high up in the URL location hierarchy that specific protected locations inherit (or some combination of the two). Since it is common for an SP to operate in the same way no matter which location triggers SAML actions, the example configuration used here places common Mellon configuration directives in the root of the hierarchy and then specific locations to be protected by Mellon can be defined with minimal directives. This strategy avoids duplicating the same parameters for each protected location.

This example has just one protected location: https://$sp_host/protected.

To configure the Mellon service provider, complete the following steps:

Some of the files referenced in the code above are created in later steps.

Creating the Service Provider Metadata

In SAML IdPs and SPs exchange SAML metadata, which is in XML format. The schema for the metadata is a standard, thus assuring participating SAML entities can consume each other’s metadata. You need:

Metadata for the IdP that the SP utilizes

Metadata describing the SP provided to the IdP

One of the components of SAML metadata is X509 certificates. These certificates are used for two purposes:

Sign SAML messages so the receiving end can prove the message originated from the expected party.

Encrypt the message during transport (seldom used because SAML messages typically occur on TLS-protected transports)

You can use your own certificates if you already have a Certificate Authority (CA) or you can generate a self-signed certificate. For simplicity in this example a self-signed certificate is used.

Because Mellon’s SP metadata must reflect the capabilities of the installed version of mod_auth_mellon, must be valid SP metadata XML, and must contain an X509 certificate (whose creation can be obtuse unless you are familiar with X509 certificate generation) the most expedient way to produce the SP metadata is to use a tool included in the mod_auth_mellon package (mellon_create_metadata.sh). The generated metadata can always be edited later because it is a text file. The tool also creates your X509 key and certificate.

SAML IdPs and SPs identify themselves using a unique name known as an EntityID. To use the Mellon metadata creation tool you need:

The EntityID, which is typically the URL of the SP, and often the URL of the SP where the SP metadata can be retrieved

The URL where SAML messages for the SP will be consumed, which Mellon calls the MellonEndPointPath.

Adding the Mellon Service Provider to the Keycloak Identity Provider

Assumption: The Keycloak IdP has already been installed on the $idp_host.

Keycloak supports multiple tenancy where all users, clients, and so on are grouped in what is called a realm. Each realm is independent of other realms. You can use an existing realm in your Keycloak, but this example shows how to create a new realm called test_realm and use that realm.

All these operations are performed using the Keycloak administration web console. You must have the admin username and password for $idp_host.

To complete the following steps:

Open the Admin Console and log on by entering the admin username and password.

After logging into the administration console there will be an existing realm. When Keycloak is first set up a root realm, master, is created by default. Any previously created realms are listed in the upper left corner of the administration console in a drop-down list.

From the realm drop-down list select Add realm.

In the Name field type test_realm and click Create.

Adding the Mellon Service Provider as a Client of the Realm

In Keycloak SAML SPs are known as clients. To add the SP we must be in the Clients section of the realm.

Click the Clients menu item on the left and click Create in the upper right corner to create a new client.

Adding the Mellon SP Client

To add the Mellon SP client, complete the following steps:

Set the client protocol to SAML. From the Client Protocol drop down list, select saml.

Provide the Mellon SP metadata file created above (/etc/httpd/saml2/mellon_metadata.xml). Depending on where your browser is running you might have to copy the SP metadata from $sp_host to the machine on which your browser is running so the browser can find the file.

Click Save.

Editing the Mellon SP Client

There are several client configuration parameters we suggest setting:

Ensure "Force POST Binding" is On.

Add paosResponse to the Valid Redirect URIs list:

Copy the postResponse URL in "Valid Redirect URIs" and paste it into the empty add text fields just below the "+".

Change "postResponse" to "paosResponse". (The paosResponse URL is needed for SAML ECP.)

Click Save at the bottom.

Many SAML SPs determine authorization based on a user’s membership in a group. The Keycloak IdP can manage user group information but it does not supply the user’s groups unless the IdP is configured to supply it as a SAML attribute.

To configure the IdP to supply the user’s groups as as a SAML attribute, complete the following steps:

Click the Mappers tab of the client.

In the upper right corner of the Mappers page, click Create.

From the Mapper Type drop-down list select Group list.

Set Name to "group list."

Set the SAML attribute name to "groups."

Click Save.

The remaining steps are performed on $sp_host.

Retrieving the Identity Provider Metadata

Now that you have created the realm on the IdP you need to retrieve the IdP metadata associated with it so the Mellon SP recognizes it. In the /etc/httpd/conf.d/mellon.conf file created previously, the MellonIdPMetadataFile is specified as /etc/httpd/saml2/idp_metadata.xml but until now that file has not existed on $sp_host. To get that file we will retrieve it from the IdP.

Retrieve the file from the IdP by substituting $idp_host with the correct value:

Configtest is equivalent to the -t argument to apachectl. If the configuration test shows any errors, correct them before proceeding.

Restart the Apache server:

systemctl restart httpd.service

You have now set up both Keycloak as a SAML IdP in the test_realm and mod_auth_mellon as SAML SP protecting the URL $sp_host/protected (and everything beneath it) by authenticating against the $idp_host IdP.

4.1. Docker Registry Configuration File Installation

For users with more advanced docker registry configurations, it is generally recommended to provide your own registry configuration file. The Keycloak docker provider supports this mechanism via the Registry Config File Format Option. Choosing this option will generate output similar to the following:

This output can then be copied into any existing registry config file. See the registry config file specification for more information on how the file should be set up, or start with href:https://github.com/docker/distribution/blob/master/cmd/registry/config-example.yml[a basic example].

Don’t forget to configure the rootcertbundle field with the location of the Keycloak realm’s pulic certificate. The auth configuration will not work without this argument.

4.2. Docker Registry Environment Variable Override Installation

Often times it is appropriate to use a simple environment variable override for develop or POC Docker registries. While this approach is usually not recommended for production use, it can be helpful when one requires quick-and-dirty way to stand up a registry. Simply use the Variable Override Format Option from the client installation tab, and an output should appear like the one below:

Don’t forget to configure the REGISTRY_AUTH_TOKEN_ROOTCERTBUNDLE override with the location of the Keycloak realm’s pulic certificate. The auth configuration will not work without this argument.

4.3. Docker Compose YAML File

This installation method is meant to be an easy way to get a docker registry authenticating against a keycloak server. It is intended for development purposes only and should never be used in a production or production-like environment.

The zip file installation mechanism provides a quickstart for developers who want to understand how the keycloak server can interact with the docker registry. In order to configure:

From the desired realm, create a client configuration. At this point you won’t have a docker registry - the quickstart will take care of that part.

Choose the "Docker Compose YAML" option from the installation tab and download the .zip file

Unzip the archive to the desired location, and open the directory.

Start the docker registry with docker-compose up

INFO: it is recommended that you configure the docker registry client in a realm other than 'master', since the HTTP Basic auth flow will not present forms.

Once the above configuration has taken place, and the keycloak server and docker registry are running, docker authentication should be successful:

5. Client Registration

In order for an application or service to utilize Keycloak it has to register a client in Keycloak.
An admin can do this through the admin console (or admin REST endpoints), but clients can also register themselves through the Keycloak client
registration service.

The following sections will describe how to use the different providers.

5.1. Authentication

To invoke the Client Registration Services you usually need a token. The token can be a bearer token, an initial access token or a registration access token.
There is an alternative to register new client without any token as well, but then you need to configure Client Registration Policies (see below).

5.1.1. Bearer Token

The bearer token can be issued on behalf of a user or a Service Account. The following permissions are required to invoke the endpoints (see Server Administration Guide for more details):

create-client or manage-client - To create clients

view-client or manage-client - To view clients

manage-client - To update or delete client

If you are using a bearer token to create clients it’s recommend to use a token from a Service Account with only the create-client role (see Server Administration Guide for more details).

5.1.2. Initial Access Token

The recommended approach to registering new clients is by using initial access tokens.
An initial access token can only be used to create clients and has a configurable expiration as well as a configurable limit on how many clients can be created.

An initial access token can be created through the admin console.
To create a new initial access token first select the realm in the admin console, then click on Realm Settings in the menu on the left, followed by
Client Registration in the tabs displayed in the page. Then finally click on Initial Access Tokens sub-tab.

You will now be able to see any existing initial access tokens. If you have access you can delete tokens that are no longer required. You can only retrieve the
value of the token when you are creating it. To create a new token click on Create. You can now optionally add how long the token should be valid, also how
many clients can be created using the token. After you click on Save the token value is displayed.

It is important that you copy/paste this token now as you won’t be able to retrieve it later. If you forget to copy/paste it, then delete the token and create another one.

The token value is used as a standard bearer token when invoking the Client Registration Services, by adding it to the Authorization header in the request.
For example:

Authorization: bearer eyJhbGciOiJSUz...

5.1.3. Registration Access Token

When you create a client through the Client Registration Service the response will include a registration access token.
The registration access token provides access to retrieve the client configuration later, but also to update or delete the client.
The registration access token is included with the request in the same way as a bearer token or initial access token.
Registration access tokens are only valid once when it’s used the response will include a new token.

If a client was created outside of the Client Registration Service it won’t have a registration access token associated with it.
You can create one through the admin console. This can also be useful if you loose the token for a particular client.
To create a new token find the client in the admin console and click on Credentials. Then click on Generate registration access token.

5.2. Keycloak Representations

The default client registration provider can be used to create, retrieve, update and delete a client.
It uses Keycloak Client Representation format which provides support for configuring clients exactly as they can be configured through the admin
console, including for example configuring protocol mappers.

To create a client create a Client Representation (JSON) then perform an HTTP POST request to /realms/<realm>/clients-registrations/default.

It will return a Client Representation that also includes the registration access token.
You should save the registration access token somewhere if you want to retrieve the config, update or delete the client later.

To retrieve the Client Representation perform an HTTP GET request to /realms/<realm>/clients-registrations/default/<client id>.

5.3. Keycloak Adapter Configuration

The installation client registration provider can be used to retrieve the adapter configuration for a client.
In addition to token authentication you can also authenticate with client credentials using HTTP basic authentication.
To do this include the following header in the request:

Authorization: basic BASE64(client-id + ':' + client-secret)

To retrieve the Adapter Configuration then perfrom an HTTP GET request to /realms/<realm>/clients-registrations/install/<client id>.

No authentication is required for public clients.
This means that for the JavaScript adapter you can load the client configuration directly from Keycloak using the above URL.

5.4. OpenID Connect Dynamic Client Registration

The endpoint to use these specifications to register clients in Keycloak is /realms/<realm>/clients-registrations/openid-connect[/<client id>].

This endpoints can also be found in the OpenID Connect Discovery endpoint for the realm, /realms/<realm>/.well-known/openid-configuration.

5.5. SAML Entity Descriptors

The SAML Entity Descriptor endpoint only supports using SAML v2 Entity Descriptors to create clients.
It doesn’t support retrieving, updating or deleting clients.
For those operations the Keycloak representation endpoints should be used.
When creating a client a Keycloak Client Representation is returned with details about the created client, including a registration access token.

To create a client perform an HTTP POST request with the SAML Entity Descriptor to /realms/<realm>/clients-registrations/saml2-entity-descriptor.

5.6. Example using CURL

The following example creates a client with the clientId myclient using CURL. You need to replace eyJhbGciOiJSUz…​ with a proper initial access token or
bearer token.

5.7. Example using Java Client Registration API

The Client Registration Java API makes it easy to use the Client Registration Service using Java.
To use include the dependency org.keycloak:keycloak-client-registration-api:>VERSION< from Maven.

For full instructions on using the Client Registration refer to the JavaDocs.
Below is an example of creating a client. You need to replace eyJhbGciOiJSUz…​ with a proper initial access token or bearer token.

5.8. Client Registration Policies

Keycloak currently supports 2 ways how can be new clients registered through Client Registration Service.

Authenticated requests - Request to register new client must contain either Initial Access Token or Bearer Token as mentioned above.

Anonymous requests - Request to register new client doesn’t need to contain any token at all

Anonymous client registration requests are very interesting and powerful feature, however you usually don’t want that anyone is able to register new
client without any limitations. Hence we have Client Registration Policy SPI, which provide a way to limit who can register new clients and under which conditions.

In Keycloak admin console, you can click to Client Registration tab and then Client Registration Policies sub-tab. Here you will see what policies
are configured by default for anonymous requests and what policies are configured for authenticated requests.

The anonymous requests (requests without any token) are allowed just for creating (registration) of new clients. So when you register
new client through anonymous request, the response will contain Registration Access Token, which must be used for Read, Update or Delete request of particular client.
However using this Registration Access Token from anonymous registration will be then subject to Anonymous Policy too! This means that for example request for update
client also needs to come from Trusted Host if you have Trusted Hosts policy. Also for example it won’t be allowed to disable Consent Required when updating client and
when Consent Required policy is present etc.

Currently we have these policy implementations:

Trusted Hosts Policy - You can configure list of trusted hosts and trusted domains. Request to Client Registration Service can be sent just from those hosts or domains.
Request sent from some untrusted IP will be rejected. URLs of newly registered client must also use just those trusted hosts or domains. For example it won’t be allowed
to set Redirect URI of client pointing to some untrusted host. By default, there is not any whitelisted host, so anonymous client registration is de-facto disabled by default.

Consent Required Policy - Newly registered clients will have Consent Allowed switch enabled. So after successful authentication, user will always
see consent screen when he needs to approve personal info and permissions (protocol mappers and roles). It means that client won’t have access to any personal
info or permission of user unless user approves it.

Protocol Mappers Policy - Allows to configure list of whitelisted protocol mapper implementations. New client can’t be registered
or updated if it contains some non-whitelisted protocol mapper. Note that this policy is used for authenticated requests as well, so
even for authenticated request there are some limitations which protocol mappers can be used.

Client Template Policy - Allow to whitelist Client Templates, which can be used with newly registered or updated clients.
There are no whitelisted templates by default.

Full Scope Policy - Newly registered clients will have Full Scope Allowed switch disabled. This means they won’t have any scoped
realm roles or client roles of other clients.

Max Clients Policy - Rejects registration if current number of clients in the realm is same or bigger than specified limit. It’s 200 by default for anonymous registrations.

Client Disabled Policy - Newly registered client will be disabled. This means that admin needs to manually approve and enable all newly registered clients.
This policy is not used by default even for anonymous registration.

6. Client Registration CLI

The Client Registration CLI is a command-line interface (CLI) tool for application developers to configure new clients in a self-service manner when integrating with Keycloak. It is specifically designed to interact with Keycloak Client Registration REST endpoints.

It is necessary to create or obtain a client configuration for any application to be able to use Keycloak. You usually configure a new client for each new application hosted on a unique host name. When an application interacts with Keycloak, the application identifies itself with a client ID so Keycloak can provide a login page, single sign-on (SSO) session management, and other services.

You can configure application clients from a command line with the Client Registration CLI, and you can use it in shell scripts.

To allow a particular user to use Client Registration CLI the Keycloak administrator typically uses the Admin Console to configure a new user with proper roles or to configure a new client and client secret to grant access to the Client Registration REST API.

6.1. Configuring a new regular user for use with Client Registration CLI

If you want to use an existing user, select that user to edit; otherwise, create a new user.

Select Role Mappings > Client Roles > realm-management. If you are in the master realm, select NAME-realm, where NAME is the name of the target realm. You can grant access to any other realm to users in the master realm.

Select Available Roles > manage-client to grant a full set of client management permissions. Another option is to choose view-clients for read-only or create-client to create new clients.

It is possible to not assign any realm-management roles to a user. In that case, a user can still log in with the Registration Client CLI but cannot use it without an Initial Access Token. Trying to perform any operations without a token results in a 403 Forbidden error.

6.2. Configuring a client for use with the Client Registration CLI

By default, the server recognizes the Client Registration CLI as the admin-cli client, which is configured automatically for every new realm. No additional client configuration is necessary when logging in with a user name.

Strengthen the security by configuring the client Access Type as Confidential and selecting Credentials > ClientId and Secret.

Provide a secret when running kcreg config credentials by using the --secret option.

Create a new client (for example, reg-cli) if you want to use a separate client configuration for the Registration Client CLI.

Enable service accounts if you want to use a service account associated with the client by selecting a client to edit in the Clients section of the Admin Console.

Under Settings, change the Access Type to Confidential, toggle the Service Accounts Enabled setting to On, and click Save.

You can configure either Client Id and Secret or Signed JWT under the Credentials tab .

With the service account enabled, you can omit specifying the user when running kcreg config credentials and only provide the client secret or keystore information.

6.3. Installing the Client Registration CLI

The Client Registration CLI is packaged inside the Keycloak Server distribution. You can find execution scripts inside the bin directory. The Linux script is called kcreg.sh, and the Windows script is called kcreg.bat.

Add the Keycloak server directory to your PATH when setting up the client for use from any location on the file system .

For example, on:

Linux:

$ export PATH=$PATH:$KEYCLOAK_HOME/bin
$ kcreg.sh

Windows:

c:\> set PATH=%PATH%;%KEYCLOAK_HOME%\bin
c:\> kcreg

KEYCLOAK_HOME refers to a directory where the Keycloak Server distribution was unpacked.

In a production environment, Keycloak has to be accessed with https: to avoid exposing tokens to network sniffers.

If a server’s certificate is not issued by one of the trusted certificate authorities (CAs) that are included in Java’s default certificate truststore, prepare a truststore.jks file and instruct the Client Registration CLI to use it.

6.4.1. Logging in

Specify a server endpoint URL and a realm when you log in with the Client Registration CLI.

Specify a user name or a client id, which results in a special service account being used. When using a user name, you must use a password for the specified user. When using a client ID, you use a client secret or a Signed JWT instead of a password.

Regardless of the login method, the account that logs in needs proper permissions to be able to perform client registration operations. Keep in mind that any account in a non-master realm can only have permissions to manage clients within the same realm. If you need to manage different realms, you can either configure multiple users in different realms, or you can create a single user in the master realm and add roles for managing clients in different realms.

You cannot configure users with the Client Registration CLI. Use the Admin Console web interface or the Admin Client CLI to configure users. See Server Administration Guide for more details.

When kcreg successfully logs in, it receives authorization tokens and saves them in a private configuration file so the tokens can be used for subsequent invocations. See Working with alternative configurations for more information on configuration files.

See the built-in help for more information on using the Client Registration CLI.

For example, on:

Linux:

$ kcreg.sh help

Windows:

c:\> kcreg help

See kcreg config credentials --help for more information about starting an authenticated session.

6.4.2. Working with alternative configurations

By default, the Client Registration CLI automatically maintains a configuration file at a default location, ./.keycloak/kcreg.config, under the user’s home directory. You can use the --config option to point to a different file or location to mantain multiple authenticated sessions in parallel. It is the safest way to perform operations tied to a single configuration file from a single thread.

Do not make the configuration file visible to other users on the system. The configuration file contains access tokens and secrets that should be kept private.

You might want to avoid storing secrets inside a configuration file by using the --no-config option with all of your commands, even thought it is less convenient and requires more token requests to do so. Specify all authentication information with each kcreg invocation.

6.4.3. Initial Access and Registration Access Tokens

Developers who do not have an account configured at the Keycloak server they want to use can use the Client Registration CLI. That is possible when the realm administrator issues a developer an Initial Access Token. It is up to the realm administrator to decide how to issue and distribute these tokens. The realm administrator can limit the maximum age of the Initial Access Token and the total number of clients that can be created with it.

Once a developer has an Initial Access Token, the developer can use it to create new clients without authenticating with kcreg config credentials. The Initial Access Token can be stored in the configuration file or specified as part of the kcreg create command.

When using an Initial Access Token, the server response includes a newly issued Registration Access Token. Any subsequent operation for that client needs to be performed by authenticating with that token, which is only valid for that client.

The Client Registration CLI automatically uses its private configuration file to save and use this token with its associated client. As long as the same configuration file is used for all client operations, the developer does not need to authenticate to read, update, or delete a client that was created this way.

See Client Registration for more information about Initial Access and Registration Access Tokens.

Run the kcreg config initial-token --help and kcreg config registration-token --help commands for more information on how to configure tokens with the Client Registration CLI.

6.4.4. Creating a client configuration

The first task after authenticating with credentials or configuring an Initial Access Token is usually to create a new client. Often you might want to use a prepared JSON file as a template and set or override some of the attributes.

The following example shows how to read a JSON file, override any client id it may contain, set any other attributes, and print the configuration to a standard output after successful creation.

Run the kcreg create --help for more information about the kcreg create command.

You can use kcreg attrs to list available attributes. Keep in mind that many configuration attributes are not checked for validity or consistency. It is up to you to specify proper values. Remember that you should not have any id fields in your
template and should not specify them as arguments to the kcreg create command.

6.4.5. Retrieving a client configuration

You can retrieve an existing client by using the kcreg get command.

For example, on:

Linux:

$ kcreg.sh get myclient

Windows:

C:\> kcreg get myclient

You can also retrieve the client configuration as an adapter configuration file, which you can package with your web application.

For example, on:

Linux:

$ kcreg.sh get myclient -e install > keycloak.json

Windows:

C:\> kcreg get myclient -e install > keycloak.json

Run the kcreg get --help command for more information about the kcreg get command.

6.4.6. Modifying a client configuration

There are two methods for updating a client configuration.

One method is to submit a complete new state to the server after getting the current configuration, saving it to a file, editing it, and posting it back to the server.

The second method fetches the current client, sets or deletes fields on it, and posts it back in one step.

For example, on:

Linux:

$ kcreg.sh update myclient -s enabled=false -d redirectUris

Windows:

C:\> kcreg update myclient -s enabled=false -d redirectUris

You can also use a file that contains only changes to be applied so you do not have to specify too many values as arguments. In this case, specify --merge to tell the Client Registration CLI that rather than treating the JSON file as a full, new configuration, it should treat it as a set of attributes to be applied over the existing configuration.

For example, on:

Linux:

$ kcreg.sh update myclient --merge -d redirectUris -f mychanges.json

Windows:

C:\> kcreg update myclient --merge -d redirectUris -f mychanges.json

Run the kcreg update --help command for more information about the kcreg update command.

6.4.7. Deleting a client configuration

Use the following example to delete a client.

Linux:

$ kcreg.sh delete myclient

Windows:

C:\> kcreg delete myclient

Run the kcreg delete --help command for more information about the kcreg delete command.

6.4.8. Refreshing invalid Registration Access Tokens

When performing a create, read, update, and delete (CRUD) operation using the --no-config mode, the Client Registration CLI cannot handle Registration Access Tokens for you. In that case, it is possible to lose track of the most recently issued Registration Access Token for a client, which makes it impossible to perform any further CRUD operations on that client without authenticating with an account that has manage-clients permissions.

If you have permissions, you can issue a new Registration Access Token for the client and have it printed to a standard output or saved to a configuration file of your choice. Otherwise, you have to ask the realm administrator to issue a new Registration Access Token for your client and send it to you. You can then pass it to any CRUD command via the --token option. You can also use the kcreg config registration-token command to save the new token in a configuration file and have the Client Registration CLI automatically handle it for you from that point on.

Run the kcreg update-token --help command for more information about the kcreg update-token command.

6.5. Troubleshooting

Q: When logging in, I get an error: *Parameter client_assertion_type is missing [invalid_client].

A: This error means your client is configured with Signed JWT token credentials, which means you have to use the --keystore parameter when logging in.

7. Token Exchange

In Keycloak, token exchange is the process of using a set of credentials or token to obtain an entirely different token.
A client may want to invoke on a less trusted application so it may want to downgrade the current token it has.
A client may want to exchange a {project_token} for a token stored for a linked social provider account.
You may want to trust external tokens minted by other Keycloak realms or foreign IDPs. A client may have a need
to impersonate a user. Here’s a short summary of the current capabilities of Keycloak around token exchange.

A client can exchange an existing Keycloak token created for a specific client for a new token targeted to a different client

A client can exchange an existing Keycloak token for an external token, i.e. a linked Facebook account

A client can exchange an external token for a Keycloak token.

A client can impersonate a user

Token exchange in Keycloak is a very loose implementation of the OAuth Token Exchange specification at the IETF.
We have extended it a little, ignored some of it, and loosely interpreted other parts of the specification. It is
a simple grant type invocation on a realm’s OpenID Connect token endpoint.

/realms/{realm}/protocol/openid-connect/token

It accepts form parameters (application/x-www-form-urlencoded) as input and the output depends on the type of token you requested an exchange for.
Token exchange is a client endpoint so requests must provide authentication information for the calling client.
Public clients specify their client identifier as a form parameter. Confidential clients can also use form parameters
to pass their client id and secret, Basic Auth, or however your admin has configured the client authentication flow in your
realm. Here’s a list of form parameters

client_id

REQUIRED MAYBE. This parameter is required for clients using form parameters for authentication. If you are using
Basic Auth, a client JWT token, or client cert authentication, then do not specify this parameter.

client_secret

REQUIRED MAYBE. This parameter is required for clients using form parameters for authentication and using a client secret as a credential.
Do not specify this parameter if client invocations in your realm are authenticated by a different means.

grant_type

REQUIRED. The value of the parameter must be urn:ietf:params:oauth:grant-type:token-exchange.

subject_token

OPTIONAL. A security token that represents the identity of the party on behalf of whom the request is being made. It is required if you are exchanging an existing token for a new one.

subject_issuer

OPTIONAL. Identifies the issuer of the subject_token. It can be left blank if the token comes from the current realm or if the issuer
can be determined from the subject_token_type. Otherwise it is required to be specified. Valid values are the alias of an Identity Provider configured for your realm. Or an issuer claim identifier
configured by a specific Identity Provider.

subject_token_type

OPTIONAL. This parameter is the type of the token passed with the subject_token parameter. This defaults
to urn:ietf:params:oauth:token-type:access_token if the subject_token comes from the realm and is an access token.
If it is an external token, this parameter may or may not have to be specified depending on the requirements of the
subject_issuer.

requested_token_type

OPTIONAL. This parameter represents the type of token the client wants to exchange for. Currently only oauth
and OpenID Connect token types are supported. The default value for this depends on whether the
is urn:ietf:params:oauth:token-type:refresh_token in which case you will be returned both an access token and refresh
token within the response. Other appropriate values are urn:ietf:params:oauth:token-type:access_token and urn:ietf:params:oauth:token-type:id_token

audience

OPTIONAL. This parameter specifies the target client you want the new token minted for.

requested_issuer

OPTIONAL. This parameter specifies that the client wants a token minted by an external provider. It must
be the alias of an Identity Provider configured within the realm.

requested_subject

OPTIONAL. This specifies a username or user id if your client wants to impersonate a different user.

scope

NOT IMPLEMENTED. This parameter represents the target set of OAuth and OpenID Connect scopes the client
is requesting. It is not implemented at this time but will be once Keycloak has better support for
scopes in general.

We currently only support OpenID Connect and OAuth exchanges. Support for SAML based clients and identity providers may be added in the future depending on user demand.

A successful response from an exchange invocation will return the HTTP 200 response code with a content type that
depends on the requested-token-type and requested_issuer the client asks for. OAuth requested token types will return
a JSON document as described in the OAuth Token Exchange specification.

Clients requesting a refresh token will get back both an access and refresh token in the response. Clients requesting only
access token type will only get an access token in the response. Expiration information may or may not be included for
clients requesting a an external issuer through the `requested_issuer`paramater.

Error responses generally fall under the 400 HTTP response code category, but other error status codes may be returned
depending on the severity of the error. Error responses may include content depending on the requested_issuer.
OAuth based exchanges may return a JSON document as follows:

{
"error" : "...."
"error_description" : "...."
}

Additional error claims may be returned depending on the exchange type. For example, OAuth Identity Providers may include
an additional account-link-url claim if the user does not have a link to an identity provider. This link can be used
for a client initiated link request.

Token exchange setup requires knowledge of fine grain admin permissions (See the Server Administration Guide for more information). You will need to grant clients
permission to exchange. This is discussed more later in this chapter.

The rest of this chapter discusses the setup requirements and provides examples for different exchange scenarios.
For simplicity’s sake, let’s call a token minted by the current realm as an internal token and a token minted by
an external realm or identity provider as an external token.

7.1. Internal Token to Internal Token Exchange

With an internal token to token exchange you have an existing token minted to a specific client and you want to exchange
this token for a new one minted for a different target client. Why would you want to do this? This generally happens
when a client has a token minted for itself, and needs to make additional requests to other applications that require different
claims and permissions within the access token. Other reasons this type of exchange might be required is if you
need to perform a "permission downgrade" where your app needs to invoke on a less trusted app and you don’t want
to propagate your current access token.

7.1.1. Granting Permission for the Exchange

Clients that want to exchange tokens for a different client need to be authorized in the admin console to do so.
You’ll need to define a token-exchange fine grain permission in the target client you want permission to exchange to.

Target Client Permission

Toggle the Permissions Enabled switch to true.

Target Client Permission

You should see a token-exchange link on the page. Click that to start defining the permission. It will bring you
to this page.

Target Client Exchange Permission Setup

You’ll have to define a policy for this permission. Click the Authorization link, go to the Policies tab and create
a Client Policy.

Client Policy Creation

Here you enter in the starting client, that is the authenticated client that is requesting a token exchange. After you
create this policy, go back to the target client’s token-exchange permission and add the client policy you just
defined.

Apply Client Policy

Your client now has permission to invoke. If you do not do this correctly, you will get a 403 Forbidden response if you
try to make an exchange.

7.1.2. Making the Request

When your client is exchanging an existing token for a token targeting another client, you must use the audience parameter.
This parameter must be the client identifier for the target client that you configured in the admin console.

The subject_token parameter must be an access token for the target realm. If your requested_token_type parameter
is a refresh token type, then the response will contain both an access token, refresh token, and expiration. Here’s
an example JSON response you get back from this call.

7.2. Internal Token to External Token Exchange

You can exchange a realm token for an externl token minted by an external identity provider. This external identity provider
must be configured within the Identity Provider section of the admin console. Currently only OAuth/OpenID Connect based external
identity providers are supported, this includes all social providers. Keycloak does not perform a backchannel exchange to the external provider. So if the account
is not linked, you will not be able to get the external token. To be able to obtain an external token one of
these conditions must be met:

The user must have logged in with the external identity provider at least once

The user must have linked with the external identity provider through the User Account Service

Finally, the external identity provider must have been configured to store tokens, or, one of the above actions must
have been performed with the same user session as the internal token you are exchanging.

If the account is not linked, the exchange response will contain a link you can use to establish it. This is
discussed more in the Making the Request section.

7.2.1. Granting Permission for the Exchange

Internal to external token exchange requests will be denied with a 403, Forbidden response until you grant
permission for the calling client to exchange tokens with the external identity provider. To grant permission
to the client you must go to the identity provider’s configuration page to the Permissions tab.

Identity Provider Permission

Toggle the Permissions Enabled switch to true.

Identity Provider Permission

You should see a token-exchange link on the page. Click that to start defining the permission. It will bring you
to this page.

Identity Provider Exchange Permission Setup

You’ll have to define a policy for this permission. Click the Authorization link, go to the Policies tab and create
a Client Policy.

Client Policy Creation

Here you enter in the starting client, that is the authenticated client that is requesting a token exchange. After you
create this policy, go back to the identity providers’s token-exchange permission and add the client policy you just
defined.

Apply Client Policy

Your client now has permission to invoke. If you do not do this correctly, you will get a 403 Forbidden response if you
try to make an exchange.

7.2.2. Making the Request

When your client is exchanging an existing internal token to an external one, you must provide the
requested_issuer parameter. The parameter must be the alias of a configured identity provider.

The subject_token parameter must be an access token for the target realm. The requested_token_type parameter
must be urn:ietf:params:oauth:token-type:access_token or left blank. No other requested token type is supported
at this time. Here’s
an example successful JSON response you get back from this call.

The error claim will be either token_expired or not_linked. The account-link-url claim is provided
so that the client can perform Client Initiated Account Linking. Most (all?)
providers are requiring linking through browser OAuth protocol. With the account-link-url just add a redirect_uri
query parameter to it and you can forward browsers to perform the link.

7.3. External Token to Internal Token Exchange

You can trust and exchange external tokens minted by external identity providers for internal tokens. This can be
used to bridge between realms or just to trust tokens from your social provider. It works similarly to an identity provider
browser login in that a new user is imported into your realm if it doesn’t exist.

The current limitation on external token exchanges is that if the external token maps to an existing user an
exchange will not be allowed unless the existing user already has an account link to the external identity
provider.

When the exchange is complete, a user session will be created within the realm, and you will receive an access
and or refresh token depending on the requested_token_type parameter value. You should note that this new
user session will remain active until it times out or until you call the logout endpoint of the realm passing this
new access token.

These types of changes required a configured identity provider in the admin console.

SAML identity providers are not supported at this time. Twitter tokens cannot be exchanged either.

7.3.1. Granting Permission for the Exchange

Before external token exchanges can be done, you must grant permission for the calling client to make the exchange. This
permission is granted in the same manner as interal to external permission is granted.

If you also provide an audience parameter whose value points to a different client other than the calling one, you
must also grant the calling client permission to exchange to the target client specific in the audience parameter. How
to do this is discussed earlier in this section.

7.3.2. Making the Request

The subject_token_type must either be urn:ietf:params:oauth:token-type:access_token or urn:ietf:params:oauth:token-type:jwt.
If the type is urn:ietf:params:oauth:token-type:access_token you must specify the subject_issuer parameter and it must be the
alias of the configured identity provider. If the type is urn:ietf:params:oauth:token-type:jwt, the provider will be matched via
the issuer claim within the JWT which must be the alias of the provider, or a registered issuer within the providers configuration.

For validation, if the token is an access token, the provider’s user info service will be invoked to validate the token. A successful call
will mean that the access token is valid. If the subject token is a JWT and if the provider has signature validation enabled, that will be attempted,
otherwise, it will default to also invoking on the user info service to validate the token.

By default, the internal token minted will use the calling client to determine what’s in the token using the protocol
mappers defined for the calling client. Alternatively, you can specify a different target client using the audience
parameter.

If your requested_token_type parameter
is a refresh token type, then the response will contain both an access token, refresh token, and expiration. Here’s
an example JSON response you get back from this call.

7.4. Impersonation

For internal and external token exchanges, the client can request on behalf of a user to impersonate a different user.
For example, you may have an admin application that needs to impersonate a user so that a support engineer can debug
a problem.

7.4.1. Granting Permission for the Exchange

The user that the subject token represents must have permission to impersonate other users. See the
Server Administration Guide on how to enable this permission. It can be done through a role or through
fine grain admin permissions.

7.4.2. Making the Request

Make the request as described in other chapters except additionally specify the request_subject parameter. The
value of this parameter must be a username or user id.

7.5. Direct Naked Impersonation

You can make an internal token exchange request without providing a subject_token. This is called a direct
naked impersonation because it places a lot of trust in a client as that client can impersonate any user in the realm.
You might need this to bridge for applications where it is impossible to obtain a subject token to exchange. For example,
you may be integrating a legacy application that performs login directly with LDAP. In that case, the legacy app
is able to authenticate users itself, but not able to obtain a token.

It is very risky to enable direct naked impersonation for a client. If the client’s credentials are ever
stolen, that client can impersonate any user in the system.

7.5.1. Granting Permission for the Exchange

If the audience parameter is provided, then the calling client must have permission to exchange to the client. How
to set this up is discussed earlier in this chapter.

Additionally, the calling client must be granted permission to impersonate users. In the admin console, go to the
Users screen and click on the Permissions tab.

Users Permission

Toggle the Permissions Enabled switch to true.

Identity Provider Permission

You should see a impersonation link on the page. Click that to start defining the permission. It will bring you
to this page.

Users Impersonation Permission Setup

You’ll have to define a policy for this permission. Click the Authorization link, go to the Policies tab and create
a Client Policy.

Client Policy Creation

Here you enter in the starting client, that is the authenticated client that is requesting a token exchange. After you
create this policy, go back to the users' impersonation permission and add the client policy you just
defined.

Apply Client Policy

Your client now has permission to impersonate users. If you do not do this correctly, you will get a 403 Forbidden response if you
try to make this type of exchange.

Public clients are not allowed to do direct naked impersonations.

7.5.2. Making the Request

To make the request, simply specify the requested_subject parameter. This must be the username or user id of
a valid user. You can also specify an audience parameter if you wish.

7.6. Expand Permission Model With Service Accounts

When granting clients permission to exchange, you don’t necessarily have to manually enable those permissions for each and every client.
If the client has a service account associated with it, you can use a role to group permissions together and assign exchange permissions
by assigning a role to the client’s service account. For example, you might define a naked-exchange role and any service account that has that
role can do a naked exchange.

7.7. Exchange Vulnerabilities

When you start allowing token exchanges, there’s various things you have to both be aware of and careful of.

The first is public clients. Public clients do not have or require a client credential in order to perform an exchange. Anybody that has a valid
token will be able to impersonate the public client and perform the exchanges that public client is allowed to perform. If there
are any untrustworthy clients that are managed by your realm, public clients may open up vulnerabilities in your permission models.
This is why direct naked exchanges do not allow public clients and will abort with an error if the calling client is public.

It is possible to exchange social tokens provided by Facebook, Google, etc. for a realm token. Be careful and vigilante on what
the exchange token is allowed to do as its not hard to create fake accounts on these social websites. Use default roles, groups, and identity provider mappers to control what attributes and roles
are assigned to the external social user.

Direct naked exchanges are quite dangerous. You are putting a lot of trust in the calling client that it will never leak out
its client credentials. If those credentials are leaked, then the thief can impersonate anybody in your system. This is in direct
contrast to confidential clients that have existing tokens. You have two factors of authentication, the access token and the client
credentials, and you’re only dealing with one user. So use direct naked exchanges sparingly.